Thank you for your detailed response. The offset calculator @ 1010TIRES.COM - Wheel Offset Calculator indicates that if the 11" wheel has a 55 mm offset then a 12" wheel should have 68 mm offset to keep the outer position the same. 68 mm offset would require 26 mm room inside. Do you have 26 mm between the inside of your rim (not the tire's widest section but the metal of your wheel) and the shock housing? Thank you again!