[wilf leek]

Ernie - I am not sure there is actually a definitive answer to your question.

More than one thing could lead to your rear steer condition:

1/ play in the rear end somewhere

2/ incorrect alignment of rear end

3/ tyre pressures

4/ road camber

and so on.

Probably you are best to track down and eliminate the free play you have found, get the alignment (including thrust angle) checked out, and see what happens. As I said before, I don't think I have ever come across a Jag rear end where you cannot feel some play somewhere. My own included.


BTW - the spines on the outboard ends of the driveshafts are meant to be loctited into position. Not doing so can lead to fretting and wear under torque reversals. Metallurgy and engineering tolerances available when that rear end was first designed and manufactured are the reason.
Usually last thing done after setting up the rear end completely, as once it is done, you will need a press to dismantle again.