Installed a HMMWV dual voltage output alternator. 100A on the 24V side, 25A on the 12 (I think).
What a pain in the you know where. Oh lordy.
I got this alternator from Maccus a while back. My stock 60A unit died and this was the only spare I had, so I had to go ahead and install it.
First, I had to bore out a deuce pulley and then have it shortened-long story, but someone sold me a pulley that wasn't deuce (don't know what it was) and I didn't notice it wasn't correct until I'd spent $80 at a machine shop having it bored. So I had it shortened and used it. Oh well.
I bought 15' of 4G welding cable and soldered lugs to it on both ends. I had already rebuilt my battery box last year with civvy batteries with an eye towards this eventual job, so the batteries were already offset to one end. I found an 81R battery that fir perfectly (correct height) for the alternator to feed.
Man, this alternator is heavy and fun to install. Since it was out, I went ahead and replaced the lower radiator hose.
I had to make a little jumper wire from my factory harness field wire-the factory 60A alternator field wire has a packard and this alternator uses a ring terminal, so I made a short wire to plug in so I wouldn't have to modify my factory wiring harness.
After doing all this, my recommendation to anyone who needs a lot of 12V power would be to just suck it up and buy an expensive high output converter. Much easier.
Battery box mod:
Why yes, that other switch does say "rear winch disconnect".
Alternator: