The worklights are standard H3 halogen bulbs, 12V / 35W.
There is a 55w option you can buy at the parts store; however my concern would be additional heat in the housing AND available alternator power to run them.
Without the high-output alternator option, you have 60A, which translates to about 720 watts. Keep in mind your alternator only produces those 720W at higher engine RPM and when cool. At idle, in warm conditions, it produces significantly less. 35w x 4 is already 140W burned for just front and rear work lights. Now add in 120w more for your high beams, 42w more for those "side lights" and you're already up to 302w. This doesn't take into account tail lamps, front parking lights, four way flashers, front / rear wipers, fan blower, a/c clutch, diesel fuel pump, fuel injectors, PCM, instrument cluster, stereo, etc.
There are several "plug and play" LED H3 bulbs available. However, I get the sense these really aren't necessarily "brighter" but rather just the more modern and intense white / bluish light. I don't care about that, I want more actual light.
I'll probably gamble on a set of Amazon specials, but I'm inclined to think these work lights will never be that bright as stock, even with a bulb upgrade.