The frame and K-member on 67 and newer are wider than early A-bodies. I think it’s worth a try fitting the 67-69 bumper. Another option is a Camaro bumper (I won’t tell anyone).
Actually, a lot of high end resto shops use 67-67 Camaro bumpers. Are you talking about the 4 mounting holes where the bumper mounts to the brackets? I can give you that in the morning.
