Most alignment shops or truck shops that can do gm 3500 trucks should be able to give you specs. Now how your going to be able to align it yourself without a machine will prove to be almost impossible unless you have a lot of front end experience....and even then its very difficult.
Most of the gm dealers i worked for that had fleet, could service big gm trucks.
On the stabilizer, it doesn't matter when you do it, it has no effect at all on alignment, it mostly only cushions the effect of road imperfections thru the steering wheel.
Personally, no matter what vehicle it i like to have the caster set as far positive as i can, try to keep camber about neutral or slightly negative and set the toe in a little.