76 dash in a 74 Dart?

'76 A-body is wired very differently than a 74. Both engine side and instrument panel side because its a very different layout.
thats what i was thinking.... did someone really change his entire engine and body harness, and dash...before he got it? i suppose its possible.
i do know my 74 has a ton of seatbelt interlock crap it took me forever to fully eliminate. my 75 RR had it too. If i was assembling a car from donors...i would have probably ditched the 74 wiring also.