Could it be done? Sure, with enough work. You'd have to wire a 120 volt acceptor up to the service outlet. You'd have to cut a hole in the coin door. The DBA, once set up, just sends pulses that are interpreted as coin drops. Example, insert $1, it sends 4 pulses so the door thinks 4 quarters were dropped.

It's not a 5 minute job, you'd have to hack up a door, and figure out the wiring.

You could install a "side mount" bill acceptor box on the cabinet:

http://na.suzohapp.com/amusement_products/coin_doors/40-0448-00

I don't think a modern door has the same dimensions so that's probably out... a box on the side as Ken suggested I think would be the least painful solution...

either that or just buy a change machine and put it next to your machine if you don't want to drill anything

It might be cheaper/easier/less damage or modification to an original game to get a small bill changer and break $1s and $5s into quarters.

Otherwise, go with Kens idea

Wiring a bill acceptor in is not that complex, but the door mounting would be tricky

ya get a changer, we use American changer and they have been good

ebay.com link: american changer model ac300

+1 for the changer if you can manage it. Dropping coins in a pinball machine, particularly an early solid state, brings you back to the those times. Some crazy hole hacked into your coin door, or a box mounted on the side of the machine, just isn't the same.

Keep in mind those changers hold their value. Sinking $1000 into a decent used one is pretty much money in the bank...

Our bartenders actually hit up the change machine now when they are out of quarters, which helps us keep everyone happy

-Jay