Graham,
Overlooked your request re Grease Gun Clips.
…
J.11 XK120 FHC advises 2-off BD.5211 for 669001 and subs., which is to suit C.4560 Grease Gun (Tecalemit GB.2788). Same BD.5211 is used for Mark VII supplied with same GB.2788 Grease Gun, but this time no advice of TERRY Clip model/size.
I do however have several BD.5211 original clips still rivetted onto lids of LHS Mark VII Tool Box, so easy to physically check/measure and identify from my TERRY’s period Catalogues.
They are generally of the same shape as per your photograph of three clips. All my original BD.5211 Clips, all dating from Mark VII/XK120 era, are Cadmium Plated, and have no markings/branding on them, but has two mounting holes 1/2" pitch.
Those with one single mounting hole only are shown in Terry’s Catalogues as Model 81/x, with x = 000 to 6 denoting sizes 1/4in to 2in.
Those with two mounting holes are identified as CARAVAN CLIPS, all of Model Code 1195/1, but the /1 is this time part of the model code (not size), with sizes of 1-3/4" to 6-3/4" listed as being available (1938 catalogue). Just so happens I do have a couple NOS examples, of these Model Clips, now marked TERRY’S No.1195 1-3/4"
Note, that although clearly a nominal 1-3/4" clip, the actual free standing diameter is 1-1/2", so design expects some tension/expansion holding an item (Grease Gun) of nominal 1-3/4" diameter.
A GB2788 Grease Gun is 1.455"dia, say nominal 1-7/16", thus less than smallest 1-3/4" (nominal). (actual 1-1/2" free) 1938 Catalogued Model 1195, so presumably a post-war addition to the size range (likely) or a Jaguar ‘special order’ (unlikely) or maybe a rationalisation of the single-hole Model 81/x range that does list an 81/5 (at 1-1/2" nominal) and an 81/4 (at 1-1/4" nominal).
Indeed I do have an original TERRY’S No.81/6 (as stamped on clip) that actually has two mounting holes and 1-3/4" free diameter (Whereas the cataloged No.81/6 gives a nominal 2" size)
Now as above, I do have several original BD.5211 (those I have checked are unmarked/unstamped - but I have more not yet checked), and these measure at 1-7/16" free (internal) diameter, and indeed just now checking, provides an adequate/snug grip on an actual GB2788 Grease Gun.
Now my 1941 TERRY’S Catalogue as well as listing 81/3, 81/4 and 81/5 also adds an intermediate size 81/3A at nominal 1-1/8" (3 is 1" and 4 is 1-1/4"), so I will go out on a limb and suggest by the time Jaguar ordered their BD.5211 there may well have been a two-hole 81/4A (at a nominal 1-5/8") selected as best suiting the then used GB2788 Grease Gun.
My 1959 TERRY’s Catalogue still only lists CARAVAN Clips 1195/1 as a smallest 1-3/4" size (as pictured above), so I remain happy with these Grease Gun clips, being model 81/x and pending better evidence, maybe a special order uncatalogued 81/4A (2-holes, nominal 1-5/8, actual free 1-7/16")
It is possible of course that these BD.5211 clips were not in fact made/supplied by TERRY’s (given originals are unmarked, and not apparently included in any of my period TERRY’s catalogues (1932, 1938, 1941, 1959)
My original BD.5211 clips are spring-steel Cadmium Plated - made of strip .432" wide (7/16in), with the outer end corners cut square, and not with a rounded corner as per TERRY’s 80/x, 81/x and 1195/1 model clips, but otherwise have a similar profile shape to the 80/x TERRY clips. The two holes are exactly 1/2" pitch. TERRYs were certainly the dominant supplier, but Here were of course other UK suppliers of spring clips during XK120 period, such as SALTER for instance, but I dont have anything on hand.
I dont know what is currently offered/available similar to a BD.5211, but otherwise maybe thye best solution is to source a couple original BD.5211 from a Mark VII Tool Box lid.
Exact location of Clips for GB2788 Grease Gun - you have your original holes, with pairs at 1/2" pitch to suit clips - if you get a chance, you may draw up a template to ensure correct location based on other fixed reference points. In the mean time, attached pic was just one quickly found (not great) of an original mounted GB2788 in a mid 1954 OTS…

PS. Whilst talking GB2788 Grease Guns, Jaguar Part No. C.4560, there were of course three variants supplied to Jaguar over the Mark VII/XK120/XK140 period that I call C.4560/a, C.4560/b and C.4560/c based on having three different Connectors fitted on the end of the delivery tube (Main body and end cap all the same).
Roger