That's quite an interesting machine, Andrew. Wouldn't mind one here!

When I was a boatbuilder I put a joiner and planer together on the same base, back, to back, so they could share a motor and take up less floor space. You just lifted the gravity tensioned motor and slipped the belt to the other pulley. I still have it.
Good score on the bits! Although, knowng you, I'm surprised that by now you don't have the machine apart and have machined up a new spindle with taper/chuck!