Will a 80s gl wiring harness work on a 76 gl ?

[jarron596]

Will a 1980 gl wiring harness work on a 1976 gl1000

[Whiskerfish]

It is not plug and play no.

[jarron596]

It is not plug and play no.

Is it worth buying or should I find a correct one ?

[Whiskerfish]

You would be much better off with a 75-77 version. 78 and up was quite different

[jarron596]

okay thank you

[Sidecar Bob]

It depends on what you want/need to do.

The biggest difference between the early and late 1000 harnesses is the extra wires needed for the Reserve Lighting Unit, which device is unreliable enough that Clymer included instructions on bypassing it in their manuals since at least the early '90s so most people end up doing away with it anyway.
The later harness has about half the wires and is much easier to understand if something goes wrong but because the early version has all those extra wires the connectors are different (= not plug & play).

1980 was the first year for the 1100. It would be possible to make an 1100 harness work on a 1000 of you have a very good grasp on how wiring works but again the connectors would be different, which is not insurmountable of you don't mind replacing connectors. And the 1100 came with electronic ignition instead of the 1000's points, again not difficult to deal with; I ran a 1000 engine with points in an 1100 for a long time before changing to a Dyna S ignition (basically the same wiring as the points but no condensers) and eventually going to an 1100 engine, still with the Dyna S and the same wiring as when it was a 1000.
There are other differences like the combined solid state regulator/rectifier instead of the earlier separate regulator and rectifier (a worthwhile upgrade) and a bunch of stuff the 1100 has that you don't really need (the turn signal cancelling unit comes to mind).

If you don't understand wiring and just want to get it working an early 1000 harness ('75-'77) would probably be easiest.
If you are planning on making a lot of changes to the bike's electrical system later it might be worth changing to a later harness and learning how to replace the connectors.