Well i am doing a rebuild on a motor that was frakinsteined i needed new rotors so i got S5 N/a rotors but it had 12a rotors and e-shaft and flywheel and housings. what do i need to do the build.

I have s5 Irons/housings
S5 rotors
can i use an s4 eccentric shaft flywheel and counterweight or do i need S5?

Thanks in advance

 

86-95 2 rotor shafts are all identical.