They should both have 7 wires and they should be the same between PreGen and NewGen.
Harness colors:
White is Main power from the battery.
Brown is switched power to the junction box.
Gray is power to the igniter.
Red/blue is power from the Taillight fuse.
Red is power to the taillight.
White/black is a fork off the Main power.
White/green is power to the turn signal fuse.
PreGen:
NewGen: