I finally found some wheels I am actually interested in, BBS CHR IIs, but after speaking with BBS, they said they are only meant to fit the F-Type, and with a 32ET, the wheels will stick out passed the fenders. I dont know if he is being conservative or if they really will stick out passed the fenders.

I could always go with a non-staggered setup, of course, but that isnt as fun.

So here are the wheel offsets. The first set is for the XJR with Fallon wheels, the second is for XJs with 20" wheels. Hope this will help.

Front wheel Offset 20”, 9J, 49 offset 20”, 9J, 49 offset
Rear Wheel Offset 20”, 10J, 44 offset 20”, 10J, 46 offset

Thanks a lot XJsss. So am I correct in saying that an aftermarket rear wheel with an ET32 offset would stick out 14mm more than the 20" wheels you listed above (46 offset)?

I believe so. and the tire would possibly come into contact with the body wheel opening. There have been others that have installed large wheels. so a search may give you additional information.