65' stepside beds

[ron19]

Hi all. I have a 65' c10 that came with a mid 70's bed. I just bought a 64' GMC, a little rough but bed fenders are in good shape. After doing some checking, I measured the bed dimensions from the 70's and the 64' and found them to be the same. My question is: would there be any draw backs or problems that anyone knows of, of putting the 64' fenders on the 70's box. My 70's box is in 10 times better shape than the rotted out one on the 64'. Can it really just be drilling holes in the 70's box to match the older fenders?

Any input would be great. Sorry I don't pics of them both, I will get them soon.

Info on the 65': 65 c10, lowered 2" in front 3" in back. 400 sbc w/T10 4 speed. Fat 15" tires in back, spins them when I want it too.