Ive been scouring the web for the info I need. You would think there would be tons, but not so for my particular game.
By playing around with it I did find that one of the three buttons I mentioned enters a service type screen, but not much info on it. (These buttons are small radio shack type buttons).
Another button enters a series of screens that show winnings, times each combo was hit, etc. Not sure what this is good for, book keeping I suppose.
The third button didnt appear to do anything, I figured it had to do with a ticket printer or payout hopper, even though the old cabinet had neither in it when I got it, but it could have had at one time.
I checked the button with a ohm meter and its not even working. when I shorted the contacts on it, it clears all the credits on the game. So maybe this is some kind of payout function.
I think I will mount the first two service switches inside the new cabinet, so you have to remove back cover to gain access.
im thinking of adding the third one to the back, accessible with cover on. When this game is powered off it remembers how many credits were on it when you power it back on.
this button may be useful to clear all the credits, should you want to start over.