Automatic to Manual Conversion, Again

Hi all, I’m sure these questions have been asked many times before, but I’m still learning about the Mk 2 and really appreciate any advice.

I intend to convert my 1962 Mk 2 from a BW DG250 auto to a 4-synchro manual with the short Laycock de Normanville overdrive. I’m pretty sure I know most of the mods required, including the pedal box, flywheel, propshaft, clutch actuation, OD switch, rear mount, etc. My primary concern is the transmission tunnel - does this involve some minor reshaping and cutting a hole for the shift lever? Or is it more significant? I see that both the carpets and the center console dash panels are different because of the tunnel shape.

Also, is there much difference in the layout of the late Mk2 with this arrangement vs the 420G? Does the 420G have a cast iron version of the L de N overdrive? and are the 420 gearbox mount and driveshaft different than a late model Mk2 with OD?

Really appreciate the advice as I’m sure it’s been done many times.


Hi Jason,
I performed this with my '66 ‘S’ many years ago, you will not be disappointed with the different driving dynamics.
I left the tunnel as it was which caused some problems with fitting the centre consol, IIRC I cut a hole in the tunnel and I think I sourced a cover from a wreckers, but don’t quote me on that.
The gearbox I used was from a XJ6,probably S1 with O/d and I used the XJ gearbox mount. For the o/d switch I repurposed the intermediate hold switch on the dash, so easy to operate, didn’t have to take the hand ff the steering wheel, not sure if the MK11 has that switch?
As I mentioned it was at least 25 yrs ago and I am about to start rebuilding the car as it has been off the road for the last 20 years. I probably had to modify the prop shaft but honestly cannot recall now.
Once I have the car stripped down I will entertain the idea of reshaping the tunnel to the manual floor pan so that the consol is a better fit, also the clutch pedal is positioned quite close to the tunnel. Hope this helps in some way.

I changed mine years back , cut a hole in the Auto Tunnel , and made a cover out of fiberglass , its not just a round hole , for the stick , if I remember right , some of the linkage on the top of the manual box hits the Auto tunnel , the 2 tunnels are a completely different shape , you can’t just fit a cover from the manual !
The centre console and the 2 front side covers are different to .

As you can see from the pic , the cover I made is not that big ,I had a rubber gaiter that was the right size for the job !

Many thanks Ian and Robin.
It took me a while to understand the fiberglass cover that Ian fabricated, but I have now seen some other photos of a normal manual fiberglass cover - I never new this existed since the auto has no such removable cover. I’m going to cut a hole and adapt a manual cover to the auto tunnel. I also like the idea of repurposing the intermediate speed hold switch, to keep it on the dash panel. Thanks again for the great ideas guys.

I have most of the Mk2 manual & overdrive parts you need, includung a manual centre console. Off-list is probably better, or phone: nine one zero 398 three six two zero


Like I said Jason , the tunnel’s are a completely different shape , I did offer up the manual cover , but there would be little left of it in the end , that’s when I decided to make my own , its not fiberglass to the tunnel , its held on with self tapping screws , so easy removed , if you do manage to get a manual one to fit , please post pics !

Found this pic , I have marked in white what the Auto tunnel is missing !

Here’s what the opening looks like on a manual S-Type:

And the cover:

It’s not really critical, as long as you place and size the hole for the shift lever so that it won’t limit throw (with the boot on!), and it gives you enough space to get the top cover off, then you’re ok.

Gentlemen thank you very much for the photos etc, this makes it all much clearer. I am going to fabricate some sort of cover and when I do I will post photos. Now I have some work to do!

I’m also going down the same path of converting auto to manual in a '62 Mk2 3.8. Looks like you’re several steps ahead of me though as my in-process engine rebuild means I have lots of time to work on other non-engine, non-gearbox related activities. I also investigated using the fiberglass shroud from a manual, but as Ian stated the tunnels are completely different shapes so opted not to try that as I don’t believe it would have fit anyway. I plan on fabricating something myself that will fit the auto tunnel and fit under the auto center console (which is also different, less tall, than the manual console).

On a side note, looking at the bottom of my console from my automatic it has an oval cutout…which I would assume is for a shift lever. Obviously this is covered over for the auto…but looks like Jaguar may have made the auto body shells adaptable to a manual gearbox. Anyone knowledgeable about this? The ease of changing over an auto to manual including what looks like the right gearbox mounts on the chassis and the cutout on the console could lead me to believe that Jaguar designed the auto body shell to be able to accept a manual gearbox in the event they ran short of manual body shells…or maybe made too made auto body shells. In terms of manufacturing and supply flexibility this would have been forward thinking.

If this were the case…is anyone aware of manual gearbox fitted Mk2 that came out of the factory in an auto body shell?


Hi this is my first post in this forum, I’ve browsed it as a guest for quite some time though! I converted my 1965 3.4 about 20+ years ago. I had planned the job for a few years because there’s a lot more involved than one might imagine. I was very lucky to pick up a comprehensive ‘kit’ of parts including a Moss MOD gearbox complete with bell housing, matching prop shaft, pedal box & rear mounting that was only the beginning. I went on to source a flywheel to match a coil spring clutch. I noted the automatic engines are not fitted with a spigot bearing either. Like many of the others on this interesting thread I cut a rectangular opening into the top of the transmission tunnel & designed & fabricated a cover to accommodate gear lever requirements & access to reversing light & o/d inhibitor switches as well. My fabrication was quite long so it had to include the bottom mounting of the radio panel. I obtained a manual transmission tunnel cover but only used the top portion which fitted directly to to the body of my original auto cover. The rear mounting, IIRC, picked up 6 of the original floor mounted captive nuts of the auto, the 2 inner forward ones needed holes drilling in the floor for nuts & bolts.
Anyway for my first post that will do for now, suffice to say there was a lot of other time consuming work to do but I really wanted this conversion to be as close to a standard MOD car as is reasonably possible despite the considerable differences in body structure below the skin so to speak.

This thread makes me pine for my 1967 420, return all the best stuff of small Jag sedans, including an MOD.

I bet Jaguar only made 1 centre for the console , with a hole in it , to be used on man or auto cars !

The shape of the console frame is different as the auto one has shallower sides. If you turn an auto one over you’ll see how the top just pops off with standard trim spring clips. My converted one is the original auto frame & side trims with the top off of a manual donor which was the same colour, oh & I used my original ash tray as it was in better nick. A dead giveaway of a converted auto is the shallow sided consul. There are plenty of others for those in the know! To me the main improvement of the conversion is the more relaxed cruising especially if the auto back axle is retained with the 3.54:1 diff.


Yes Ian they are shallower particularly at the front because the auto transmission tunnel is both taller & wider than the manual so the shallower sides of the consul means both types of consul are the same overall height from the floor when fitted to their respective tunnels. The tops are the same except manual has the trimmed gear lever opening and auto hasn’t.

I wish I was at the point by now of fabricating the transmission tunnel cover, but I am currently having an issue with the propshaft rubbing on the inside-top of the tunnel. I have installed a 4-syncro transmission with the Laycock de Normanville OD into my 1962 Mk2. I used the type of rear mount shown below (first image) which I believe can come from either an S-Type or a 420G. It seemed to be a good fit because it mounted to existing bolt holes from the automatic transmission mount, and the pin sticking down from the trans at least aligns with the hole and rubber bush in the mount. But the transmission is still sitting too high and the propshaft just hits the tunnel. Also, the pin is not protruding below the rubber bush. Does anybody know if I should have used a conventional 3.8 Mk2 support like the second image below? I was not certain that mount is compatible with the later OD. I have tried two different springs and the shorter softer spring resulted in the gearbox being way too low.

Many thanks all.



I’m not absolutely certain about this, but I think the Mark 2 mounting is about 3/4" deeper than the S/420. I think the peg on the S/420 trans/OD is also a bit farther back.

Are you sure you have the right spring. From memory, mine is 4-5" long. Here is a picture (for reference, the sheet of paper is A4 so the short side is 210mm):

Have you got your rear stabilizer adjusted correctly? (i.e. is the D/S hitting the tunnel because the spring is pushing the tailshaft up, or is the stabilizer holding the whole drive package at an angle.)

Here is a pic from my disassembly. See the 8 square spacers? They were between the floor pan and the rear mount. The are each about 1/8" thick. Would dropping the mount 1/4" make your D/S clear the tunnel?

I used the mount in the second image , I changed 240 Auto to 4-speed syncro , as you can see by the pic , if I used the mount in the first pic , the spring would be over the prop , if yours fits in line , just a height issue , have you got 4 number 92’s in the first pic , they look like spacers , they would lower the prop !

With the short extension O/D only the S/420 mount can be used…
As Andrew points out ,check the stabilizer ,leave it loose until everything
is mounted. I suggest changing the two front fixing setscrews/bolts to
3/8, and if need be, with nuts inside the car. I assume the rubber seat
rings for the spring are new.