I would suggest at least 2 1/2degrees caster. The camber is adjustable by bending the axle ends, but it is hard to find anyone with the bending arms, small enough for the pickup axles. Toe in with make your truck wander also. I run about 1/8 toe out on mine. Make sure you don't have the steering box too tight. It should have just a touch of free play at dead center straight ahead. If it is too tight, it won't let the wheels center up after a slight turn of the steering wheel. Find a truck shop that does truck tractor straight axle alignments, instead of a car alignment shop. Most cars shops have never aligned a straight axle vehicle.
