I would ditch the Jamma harness and go with an I-Pac and arcadevga instead. There are no wired joysticks on that panel, and the wires for them may be snipped off from the harness itself. Even if it isn't, you will still have to rewire, so you might as well do it from scratch and save the extra money.
You might also want to check and see if Championship Bowling has been dumped for emulation yet. I don't see it in Mame.
Kind of a shame that you don't have any other cabinets to use. Bowling games are pretty fun and often sell for pretty good money. Capcom Bowling has been skyrocketing in value lately. They used to sell for like $50 at the auctions, but lately they are going for much more (one on ebay now is already at $280).
Also, the old kit will probably sell for much more money if you include the control panel, marquee, trackball, PCB, harness, bezel, and all the other guts too.