I've ran into an issue once where the rad cowl mounting points are different. It was on a 72 Duster trying to mount Scamp fenders I believe; its been a long time.

"Who is John Galt?"

68 Coronet RT LL1 Auto
70 Duster 340 (yea right) FE5 4 SPD, 11.86 @ 114 MPH so far
01 2500 Quad Cab 4x4 Cummins