Rick,
Without ever having set one up, I really don't know if that's all I need.
From reading older posts, it was mentioned that there is an adapter harness to connect the MARS BV to the Bally Alpha and described it as i mentioned above.
If there's anything else involved in making one work, I wouldn't know.
But from what I can tell, that is what I need. I have the large Molex from the BV and have found the small 2 and 5 pin connectors inside the cabinet.
The machine arrived with nothing connected, so it's been interesting figuring it all out. And this should be the last piece of the puzzle.
Thank you for the reply.
Curtis ash100