cranks and pistons and rods, OH MY
the cranks will interchange as long as the top rod bearing journals are the same size.
The pins. The piston ring locating pins are moved farther apart on the 440 piston. You will be able to use the new piston in new or old cylinders.
The problem comes when you put an old piston in a new (440) cylinder. The pin will be exposed. I do not forsee those pins coming out, but the end of the ring will be exposed in the inkake. Could break the ring and trash the cylinder.
I wonder if you can open up the intake more with the new piston? Ed will know.