Are you looking to have them recoil? If so you need a recoil kit and happ recoil guns. If not then you can just make a harness for them. Happ's site should have the wiring diagram for them and a point blank manual will have the same. The wire colors are different. Mine was wired for happ and is now back to namco guns. You can wire them directly without the happ gun pcb. If you have the .45 cal recoil guns from happ then you need the gun pcb. If you want one I have a few extras somewhere.