I bought a box on ebay that was supposedly from a 2001 explorer, it was big enough and had enough spaces to put all the flashers, relays (EFI etc) and fuses in one place. It was a lot of work. I took the 87 mustang EFI harness and the Centrch Harness the PO bought plus all the winc, offroad lights, crusie control, etc and wired it into to one singal harness.
It was a lot of work but it doesnt have to be if its just basically a stock bronco with a few added accessories.
I would recommend you leave it as is or start with new wire and new connectors which basically means just buy someones harness.