very common hack from back in the day.

Yes, lazy. It *might* be more effective at getting rid of the heat generated by moving the bridge from underneath. If you're going to rebuild the board anyway reverse it, but it's fine to leave it as well if it's working.

Wait.... just noticed that only 2 wires attached to it. How is that working? Fix it properly. I guess it's only replacing one bad diode in the bridge?

This mod uses the diodes inside the extra bridge to drop the feature lamp voltage. The later bally transformers put out very high feature lamp voltage. I have seen it close to 8vdc in kings of steel which will burn out the feature lamps fast (or melt LEDs). I would measure your feature lamp bus voltage before deciding to reverse this. You may be better off leaving it in.

I think there was a major distributor that did this mod to every single one of their games. Quite common and always done in the same way.

not without adding a substantial heat sink to the feature lamp bridge. Keep it on the bottom. Use a thicker brand of bridge rectifier and it will mount underneath ok. Like GBPC3506W by Fairchild / On Semi are right size but Vishay is too thin.

*dupe*