Absolutely no one cares about that, nor should you.
Pull the head, yank the bad piston and rod, take it to a machine shop to have the big end checked and re-sized if needed. Bring the crank and have it ground undersize, buy the correct bearings for the undersize crank or buy a crankshaft kit and put it back together.
Find and replace the balance shaft and hardware. Every gasket, every rubber seal, everything made of rubber - hoses, ducts, all. Check every bit of wiring and connectors. Anything cracked, corroded or even slightly suspect, you change. If you don’t you will go insane trying to make this thing run again.