marc olivares
Adventurer
Using a locking diff would be masking the problem, not curing it, and could lead to all sorts of odd effects on different surfaces. It may have no help at all in keeping the vehicle straight after a front tyre blow out, which correct castor angle does help with.
Don't elongate the swivel housing bolt holes to do this - it's a terrible botch. Firstly, it's inaccurate, and you'll probably end up with uneven castors from side to side. Secondly, it removes a lot of material from under the bolt head (up to 40% loss) so creates a serious weakness in the joint and will likely end up at some point in the bolts shearing or the swivel flange cracking.
Do the job properly and use either castor corrected radius arms and standard bushes, or standard arms and corrected bushes.
A double cardan jointed front prop will probably be of benefit - the front UJ will have been set to a near straight position by the lift while the rear will be more steeply cranked, which will render the factory UJ phasing out of required spec. The rear is unlikely to be a problem unless you have a worn UJ/rotoflex.
wow, there is a lot of misinformation and conjecture in this post. :Wow1: