The '74 also had a seatbelt interlock system, and other starter disable wires that went out under the hood. I have the wiring schematics @ home and will let you know the major differences later if no one else chimes in.

I need a good 72 up ralley harness and am too cheap to pay the $250-300 for a new one. if you wind up not needing yours, PM me even if it needs some "work"

Todd