It's possible that you have a game board problem, and the board is putting out bad voltages to the monitor, which is causing the fuses (and possibly other stuff) to blow. In general, you never want to connect a 6100 to a game board unless you are sure the game board is putting out safe voltages, as you'll just repeatedly blow the monitor.
Test the DC and AC voltages on the XOUT and YOUT test points on the game board. You should have between 0 and 1 volt DC, and roughly 2-3V AC on each. These are not exact values, as they fluctuate a bit during the attract mode. But if you are getting more than 1.5V DC on either, there is a problem.
If that's the case, one quick check is to feel the chips in the video section with the back of your finger, with the game powered on, and the monitor disconnected. The video section is the lower right section, where the adjustment pots are. If any chips are scorching hot, they are bad, particularly the TL081's, TL082's or 1495's. You want to replace those first, and socket them.
That won't be guaranteed to fix it, as chips can be bad and not get hot, but if they're hot they're definitely bad, so start there.