I think my 79 850 is not worth trying to resurrect. the harness has been so hacked into, I cant tell where anything goes, the tailight, instrument panel, headlight bucket are alll disconnected. No front master cylinder. I think its not even a good parts bike now. But in regard to installing a replacement harness on any bike, do you first carefully remove the old one as intact as possible. then take the replacement one and try to plug and play what you can up front and somehow work your way to the back? There are coils, regulator, rectifier, signals, ignition switch, solenoid, all sort of necessary connections to make.So it it seems that a connector on the harness will match a connector on the bike side of the harness and after plugging enough things together it might work? Is that the way it goes?