How big is the trailer? Do you want the wires to go through the frame or is it okay to have them on the outside? I just zip tied them to the frame, I swear you spend as much time snaking wires through rusty trailer frame as you do wiring it up, at least with my trailer. I supposed it’s potentially more vulnerable to getting ripped off or something if it’s outside of the frame though, but even if it does, all the wiring is easy to check and work on as it’s right in front of you. And before anyone says anything, yes, I know you can normally just tape the new wires to the old ones and pull them through, didn’t work in my case :(.
I just re-wired my trailer and I live in Mahtomedi so I might be able to help. I would recommend that whatever you do, make sure you wire it well. I like to solder all connections and use the shrink wrap stuff too. Make sure you stick a ground screw into the trailer frame or something reliable so the ground doesn’t suck.
I’d also make sure you buy decent trailer light kit, make sure they are submersible and the LED ones have the added benefit of light bulbs not burning out. I think I spend ~$50 on the led kit from fleet farm.
Either way, definitely check the fuses before you do anything. My trailer lights weren’t working and I soon realized that I had blown a fuse. Then I also realized the wiring was crap and needed to be fully replaced.