These are my favorite rims, and I think I will do this or mimic True Bullitt Blue's moves with the 18" BUllitt replicas in the rear with the stock 17" rims in front. His car looks proportional with bigger tires and wheels in the rear. If I use the Cobra R 18's all around, can I run 35 series tires up front and 40 series tires in the back for some proportionality? Will they clear the front fenders(outside lips, particularly) under suspension compression? Last, but not least, I am assuming spacers will not be needed in the rear with these rims. Thanks Much! Cobra Hood being painted as we speak.