Pressurized Expansion Tank

I am running a 94 Buick [B-Body] LT1 in my 92 XJSC. Was suddenly having overheating issues after I changed the coolant, but probably because I did not “burp” the system. In the meanwhile I did some research on the LT1 reverse flow system and discovered that the system was designed with a pressurized expansion tank which was not installed. I’ve decided to add this tank but I am unsure of the proper plumbing and wiring of the sensor.
I found a diagram of the Nissan plumbing which looks right, but if anyone has either a description or diagram of how this was modified for the Jag, I’d really appreciate that.
I have no idea where to wire the sensor on the expansion tank so any help is appreciated.

On the XJS, the atmospheric recovery tank is located inside the front-aft end of the American drivers side wheel well panel.

James, I understood that was just a coolant recovery/overflow tank. Since I’m running an LT1 in my XJSC, it uses a reverse flow cooling system which employs both an expansion tank with some kind of sensor and is plumbed to bleed off steam, and a separate overflow tank.

something like this?
i suspect the sensor just goes to an idiot light on the dash to alert you to low level

Jay, I think that’s how it should be plumbed. It looks pretty similar to another diagram I found. Very helpful.

A lot depends on the radiator. Mine uses a very conventional for row brass unit. Upper and lower hose connections only.

The filler cap is plumbed in at the upper left of the radiator tank.

That cap is a pressure cap. The neck of that adapter has a spigot. A tube from that spigot goes to the ca tank.,

The t’stat housing has a bleed nipple. I did not need to use it1

Car cools perfecty.