You can adjust the caster by installing tapered shims between the axle and the springs. Toe is easy, just adjust the tie rod length. Camber changes require bending the axle, not a real problem, but it takes some special techniques and heavy jacks and chains, plus a big I-beam to anchor the axle down while you're jacking on it.
I'd suggest that you find a shop where they do alignment work on big trucks. Your little axle should present no problems at all to a shop that's accustomed to aligning a Freightliner or a Peterbilt. We bent a lot of I-beam axles at the family shop back in the 50's and 60's, but it's sort of a lost art now, along with the equipment to do the job.
Jerry
