If you just pay attention to the outer diameter of the tire you can do a lot of upgrades without messing up your computer.I have changed everything but the paint on my SS - but I am still running stock wheels - I feel they offer the best performance with the most sidewall. Just bought another set of stock wheels to have powder coated. Upgraded my tires to BFG Comp 2
That is where I am headed with my tires for this summer. The fronts and the rear BFG-Force-Comp-2, 10 inch tread width on the rear and 10.5 inch on the fronts. It looks like that is the max tread width for the stock rims.