Anybody running 17" Cobra Bullit rims on a Duster

Ok, so after reading through this wealth of information, I still have a question regarding tire size you guys are running. I have 17x8 bulliits with the 45mm offset or 6.295 backspace with 235/55/17 directly off an 06 mustang. I'm running a 66 b body rear in my 71 scamp, and the rears look and ride great. The fronts however are a little to close for comfort in the rear of the fender where it bolts, and at the top of the fender when turning hard. I'm afraid with articulation of the suspension, I'll rub. So, my question is, will a shorter diam tire resolve this? What would give me a shorter diameter overall, and maybe even a slightly narrower tread? I can also crank up my torsion bars a little to gain fender clearance.
Thanks guys, great thread