Front Swap Question (mounts)

[red450ih]

I used the search function with inconclusive results.

The Project: I want to use a 1984 4x4 Cab and front sheet metal on a 1979 4x4 frame.

The Question: Where the radiator support bolts to the frame, is there a height difference in the frame mounts (riveted to frame) between the 73-80 and 81-87 frame? What issues will I run into here? I only have a 79 K20 frame for reference for now. I'll be swaping the 1984 cab and front sheet metal as a unit and will not have to worry about the wipers and other common swap issues that I have read about. Just looking for info relating to the 1984 radiator mounting to the 1979 frame. Thanks!