Wrenchbender,

I am thinking "bicycle fork" and I see the king pin inclination tilting backwards, just like the fork on a big old chopper motorcycle. If I put the shim between the axle and the spring, with the thick part forward and the thin part to the rear, wouldn't I get this angle...I think I would. This would be positive caster!

http://en.wikipedia.org/wiki/Caster_angle

AND

http://www.procarcare.com/images/shar/encyclopedia/8852MG15.gif

Stuart