Other than the body lines in the outer sheet metal not lining up with the quarter panels, the entire nose & doors of a Charger will bolt right onto another B-Body. The rear clip & rear window will be the hardest. There are slight differences in the years between 1968, 1969 & 1970 like the 1968 having the hood bumpers mounted to the corner where the radiator support meets the inner fender instead of being on the actual fender. The other is where some of the fender mounts bolt to the left & right side of the radiator opening. I had to redrill one on each side putting a 1970 nose on a 1969 car. It's been a long time since I played around with parts swapping but that's what I remember most.