Look on the lights/bulbs for rated power. After that you can figure what you need to wire them.
The Milwaukee battery pack, was it one of the 18/20V versions? You were likely overdriving the bulb by 50%. Many years ago this was a common thing in one of my hobbies, diving. The higher end lighting on the market was very powerful and done so by overdriving the bulbs. The result was incredible light and bulbs that needed to be changed about as often as you change batteries. I'll over-simplify it a bit. Output gains are roughly linear with increases in voltage. Life expectancy decreases at an exponential rate as voltage increases. Somewhere I have published data on it, I know what book it is in, not sure where that book is. Rough numbers off memory again, 50% increase in voltage cuts bulb life to 10%. There are other things like increasing sensitivity to vibration since the filament is much closer to melting point and has less structural integrity. Nobody uses incandescent lights anymore. There was a time where the big ones went HID, then LED came in and the high output LED has taken over nearly all of the HID market. The LEDs are run pretty hard, I have a few that can only be run on low unless they are water cooled.
