mini tub
Are leaf springs in the stock location, on 3/4' offset hangers or moved into the frame rails?
I got 9" Hoosier slicks + sidewall bulges on a 10" rim to fit nicely in the wheelwell with 3/4" offset hangers. (no mini-tubs) I don't think you'll gain much without moving the springs.
Early on I had 10.5" bias slicks with 1" more rim width on the outside but I didn't like the sidewalls sticking out even though tread with was within the fender lips. Car isn't here but I have spare mounted wheels that I can measure overall witdth (sidewall buldge) and offset with the 9" slicks..