Maybe it's all in my head, but when I switched from the 5M to the 6M, I could tell a significant difference.
My 5M-GE configuration configuration consisted of an '84 engine, Pacesetter header, open-element air filter, Denso Iridium plugs/NGK wires, 2" exhaust (no cat), and a Centerforce 2 clutch.
My only additions to the 6M-GE swap was a 3" exhaust and a Rabid Chimp intake pipe.
5M-GE setup best - 15.6 @ 88.5
6M-GE setup best - 14.93 @ 90.5
A 7M crank in a 5M engine sounds like a great combination; total cost shipped was $800