*sigh* Thanks, I'll try that. But there's a reason why self-centering is a required for IVA, it's a safety feature.
I'm considering several ways to increase the caster angle. One is slotting out the holes on one of the front suspension brackets and fitting some eccentric washers, much like this:
http://www.jegs.com/i/Specialty-Prod...23765/10002/-1
Another idea is shortening the four bushes on the top wishbones by some 2.5 mm (bush tube and crush tube) and packing with washers to increase the caster angle by about 1 degree.