When I replaced mine I believe I got it from "Ground-Up Restorations", 866-358-2277, Pt. #14195. It appears to be Mfg. by "M&H Electric Fabricators, Inc.,
www.wiringharness.com I have a 68 Std Cpe and it matched great. I installed it and everything works fine. The only thing is that harness goes from under the dash inside at the firewall by the fuse block all the way to the rear, and also has a wire for the right door dome light switch that goes under the dash from the Left side to the Right side. It's up high above everything, gauges, radio, glove box, etc. There are clips up there to hold it in place. Good luck and Hope this Helps.....
Lenny