I think we cover this every week, but I like posting these pictures, I just think it looks so cool. 68 RT Coronet with 10 inchers and 4.25 back space, I'm gonna tell you it's about perfect. I have a set of 10 inch cop wheels with 5.25 backspace and the tires hit the springs on my 69 RT Charger, might work with a tire with less section width but I wouldn't go much over 4.5 back space to leave plenty of room and unless you go wider than 10 inches you will well inside the wheel well lip.