[joyridin']

There are spacers that go between the bracket and frame. One side uses a 1/4" and the other size uses maybe a 1/8". This is due to how the brackets mount on the differential. One side sits further back than the other.

The brackets are different for different model Jaguar cars. Rally made a comment about this in another post a few weeks ago and I did some investigating. The brackets are basically the same, but the mounting hole location changes position. You should be able to see the difference in the 4 holes from one set of brackets to another. This is related to how the differential originally sat in the car. To get the proper driveshaft alignment, Jaguar tipped the differential for different applications. When they tipped the differential, they still needed the lower control arms to run roughly parallel to the ground, so they changed the mounting hole locations. They also look slightly different over the years. An early Jaguar XKE set does not have the 4 holes on the bottom and the casting look a bit different. These are pretty valuable and if these the ones you have, you might consider finding a set for a later XKE and selling the early model units. I believe this is casting number: C20481. Some company was going to make them again for about $1000/set.

So yes, a set off a XJS would probably not fit an Arntz unless they originally used a XJS set. Same with your Contemporary. Rally stated he switched from a 6 degree set to a zero degree set and it improved his handling. From what I can tell, this is not possible without a fair amount of modifications. I sent him a PM about it, but he never replied.