Has anyone here swapped a 80's body on 70's frame?

How's it going.....I gotta '77 frame, finally all finished, (6-inch Skyjacker/ProComp lift, Moser shafts up front, Superior axles rear, 4.11's, Detroits, all repainted, etc) and an '84 body. I have seen a few trucks like this around, but the owners have all bought them that way, and I never really got to get a good look. So far, I know the front supports are too narrow on the frame, but I did cut the old ones off my '84 frame, but they still need to be extended a bit to bolt up to the body right. How about the cab? What needs to be done to that? And are the bed bolt holes anywhere near close?

As far as the motor, I have a '76 360 FE that was fitted into the 84 frame, and I have a bracket all made up for the hydraulic clutch to fit on the FE bellhousing, so there's one less problem gone.

Is there anything else I should know? Thanks for any help on this situation......