What do you intend to do with your trailer? Will it be a home utility trailer, always pulled behind your civvy truck(s)? Or will you be getting a deuce, CUCV, etc.?
By way of example, I don't anticipate that I'll have a mil truck anytime in the foreseeable future, and I want the trailer for just hauling stuff. I'm going to take the existing wiring harness completely out of my M101 and put a new 12V system in. If I thought I was getting a mil truck, I might do a bulb swap, or rig up new lights to the existing harness.