I am getting the bushings from Summit; about the same price as anywhere (except the local parts stores); I was combining it with some other things I needed...

Caster is like the wheel a shopping cart, more caster will cause the wheel to track "straight" the advantage is better control at higher speeds at the expense of some additional steering effort.

Our cars where designed for bias plys and they apparently did not need as much caster to track straight, so there was not that much adjustment in the orig setup...