i'm working on that but Popeye uses a 4 way joystick and the MB has 2P.
I have both main harnesses and a Popeye main harness doesn't have the wiring for P2. The MB harness doesn't have the wires on the P1 side for a 4 way stick. It only is wired for 2 way.
So yes depending on which way you go, you'll need to add wiring
I'm figuring out how to wire up my MB WB to take a 2nd cage and extension for Popeye in a 2nd cage.