Second gen wheel widths

[70rs]

Tire & wheel vendors.....or anyone with first hand experience.

I am wondering how wide I can go for tire and wheel widths inside a stock body 1970 camaro. Front and rear. (and what offset is suggested too please)

I would really like to mini tub my car, but before I make that decision I would like to know what I have to start with.
The car will be lowered. So given a nice stance, where do I end up on wheels?

Thanks!