Plans Changed! What Backspacing??

[colt zantop]

howdy everyone, well, I got a slight change of plans and I decided on not doing the mini tub. Im gonna be pushing for time taking off to school in spring and also $$ wise. so heres the question......what backspacing do I need for a 68 camaro for the rear tires to sit in as much as possible to give that "tucked" look. also, is a 9.5 the widest I can run in the rear in a stock rear wheel well??? I want a deep rear rim look and also want it tucked as much as possible.

any help would be great!