Adapter for 7 pole rv to 4 pole round?

Talk about Dingbats, Newmar has some of the best, they hung a bunch of wire off the original coach rear marker and tail light wires, but the only problem they just used 7 different wires that don't match to any wire code, most 7 wire cords are know for their colors and easy to hook up to any plug or socket.Have to start all over again to put a new 7 wire plug on, where there was only a 4 wire for the toad?????