I have put a 750 cylinder in a 600 and used the 750 2000 model pistons to get the right piston pin size. The result was 720cc and 114 rwhp ( up from 90 ish ). Head was lightly ported and the carbs had yoshimura MJN needles. I had to make new valve pockets in the pistons because of interference but other than that it was easy...
Cam chain should be the same on both as all cyl and head dimensions are the same and cam gears are interchangeable. I would take a serious look at at combustion chamber as the cylinder size is much different. Running a 600 top end on a 750 bottom with custom pistons to fit the 750 rods. The 750 rods are much more robust than the 600 and this motor is turboed. The testbed 600 made 317 hp on E-85 but lost a rod on what would have been a 200+ mph pass-- the one before was 196 in a mile.
Now I am the owner of that bike ( 600 SRAD with 750 barrels, 750 Wiseco k1 pistons and ported 600 head). I am rebuilding the engine and putting in a 750 crank and GSXR 750K1 rods. Not that it was needed because everything looked perfect even after all these years. I have honed the cylinder and putting in new rings, new bearings on crank and rods. The cc was 720, now its going to be 749cc. Hoping for 120 hp
It is NiCaSil. I have a Sunnen hone with special diamond honing stones for NiCaSil cylinders. Not cheap but well worth it when you wrench on engines as much as I do and live that far away from the rest of the world.... ( 500miles ABOVE the arctic circle ) If you are thinking about the difference in cc then its because the 750 crank has a bigger stroke than the 600.
There is a few thousands mm you can hone. I will try how many on a Hayabusa Cylinder I have . I kinda remember from a long time ago that there was something like 0,025 ~ 0,05mm ( 0,002 inch ) thickness of the NiCaSil leaving at least 0,01mm to hone. ( had too look it up : Measure Nikasil Coating Thickness on Aluminum Automotive Cylinders )