Crank identification - 060732

I've just acquired an old flywheel and the two cheek plates for a Norton twin, understanding they were for a 750 Atlas?? Commando. The flywheel has the part number 06 0732 cast into it. I've now looked through a Commando parts list and on the Andover Norton web site to try and clarify the models this crank assembly will fit but see the Commando flywheel is part 06 0731. Can any members tell me exactly what I have here please???