Add a couple more degrees of caster, most stock trucks use 2 degree. The wedge has the thickest part towards the rear of the truck. Any change to the stance of the truck will change caster angles, big and little tires, higher rear springs, etc..... I run 4 degrees in my '37 due to the front end being lower then the rear. It doesn't take much change to change the caster.
Turn the steering wheel lock to lock, if the truck doesn't raise and lower as you turn the wheel, you need more caster. It should be raise up as you past center. The raising up is the steering geometry lifting the weight of the truck, this weight lifting is what returns the steering back to center after going around a corner. To much caster makes you lift more weight each turn putting stress on you and the steering linkage. If you can't find
1 3/4" wide caster shims, buy wider ones and cut them down, the thing to watch is the leaf spring center bolt head length. The head of the bolt should pass through the wedge and locate itself in the axle.
