16x8 with 4.5" bs would give you the least rubbing. The 4.25" and 4" bs will mean you'll have to cut more than with the 4.5".
305s will fit too if you are willing to cut and trim even further.
So the calcuations are the 5.25 BS minus the 1.25 spacers plus .5 inches for the larger rim is the 4.5 " BS. is this correct thinking?
Thanks again for your help