81 GPZ550 Wiring - will a kz550 harness work?

so im having some work done on my 81 gpz550 and the wiring was a mess so i am looking for a main harness. i found a 80-83 kz550 harness on ebay and the seller said based on partzilla diagrams it would work with some minor mods so i purchased it. the guy working on my electrical is trying to get it on the bike but doesnt see how it would work.. has anyone done this job? do you know what modifications can be made to the kz550 harness to make it wor with the gpz components?

I've converted harnesses from one model to another before. It was easy, just takes some care. I unwrapped both harnesses and laid them on a table, then used the wiring schematics for both and compared. In most cases the wiring color convention carries over from one model to the next so that makes it easier. A splice here and there then rewrapping with Elliot tape and the conversion harness was good as new.

It might help to know exactly what 550 harness you got. That way you can more easily figure out the differences. see diagrams at Partzilla. The 550D GPz is probably going to have more wires & connections for the meters as it has more bulb sockets & a fuel meter. The GPz may have different electro components, maybe more, maybe less. For example the GPz has a reserve lighting device, but not a turn signal operating switch.

Edit: In addition to the main harness there are also sub wire harnesses which could be different.

Wiring diagrams. loudhvx has a motorcycle stuff page with lots of info for the KZ550. see links in his signature.
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