Shocks are sized according to the travel limits. Most things I read say to have 2/3 of total travel in compression, and 1/3 in extension. So after your spring change, you will need to measure how much actual travel the a-arms have before bottoming out. You want slightly more shock travel then you have a-arm travel so the shock never hits its internal limit. The only thing that should change with lowering ( spring change ) is chamber and maybe a little toe-in, a good alignment shop should be able to compensate for any difference. It should not effect steering effort or geometry. What you may find after the change is the ride is much stiffer, spring rates change with lower springs, they have to or it would bottom out all the time.
They are plenty of Firebird / Camaro sites that sell lower kits for the '701/2 - '81 F- bodys, so finding shocks to match the springs shouldn't be an issue, this would also be a good time to replace all the bushings if you haven't done so already. The Poly bushing kits really tighten up the front ends!
Joe
