Agree completely with 67dart273 and abodyjoe. The SKOSH chart is a good reference. For a street car on 15” rims and the usual BFG t/a’s or cooper cobras a good -.25 to -.5 degrees of camber is good. If you’ve got power steering run as much positive caster as you can get, +3 to +5 degrees is great. If you’ve got manual steering you might not want to go all the way to +5* of caster (if you can even get it) as the steering will get heavier at low speeds.
With offset bushings and stock UCA’s you probably won’t get more than +3.5* of caster anyway, that’s about all the adjustment you can get with those. With most tubular UCA’s you can usually get around +5*s. All of that depends on your ride height, some can get more, some less.
More positive caster will help with high speed stability, and it adds camber on turn in which improves handling. It also improves return to center for the wheels, the car wants to go straight if there’s no steering input. But the more you add the heavier the steering gets. With the overboosted stock power steering that’s a good thing. With manual steering you just have to decide if you can deal with the added effort. I run a fast ratio manual box and +6.5* of caster, so it’s not impossible. But some folks wouldn’t like how heavy my steering is either.