750 cylinder on 700 bottom end?

hello gents
New to the forum since Nyrock completely sh*t all over there site and let 3rd grader design it.
i smashed my bike up last winter ( here's the video, ), crushed one side of the frame and snapped the other side.
i finally found a frame so i can start switching everying over once its blasted and painted.

so while i have the motor out i have been researching the idea of replacing the 700 cylinder and piston with a 750. the prices i got to bore and re-plate the cylinder where crazy so i figured this would be the easiest way to go.

the 2013 750 has the same part number bottom end and top end as the 06 700 i have, only difference is that the 750 crank has a different part number, same connecting rod and pin but different crank, it looks like they changed the shape of the counter weight on the crank.

can anyone see any other issues i might run into doing this?

thanks guys.