Welcome to the board. You will need to notch the lower front edges to clear the gravel pan (filler panel behind the bumper, under the grille) because of the differing bumper style. Otherwise, yes, it will swap over. There is a parts interchange thread in the Tech section of the board ... a lot of good ideas here ... http://mmb.maverick.to/showthread.php?t=36031
I have fenders on my 2 door 70 that came off a 72 4 door car and they fit perfectly. As mentioned, putting later fenders on a small bumper car, the fenders must me notched for the front stone guard or the stone guard can be modified - It's been discussed here both ways