are they changable with the 77? or are do they need that year alone?

It depends. What part of the wiring harness are you talking about? There is the enging bay harness and the body harness, and those can be broken down into sub-harnesses.

im talking about the full kit and kaboodle all of it is it interchange able and if not all of it what sections are?

77 and 78 use many different functions. One example is the fuel pump switch built into the AFM. 77 Uses it, 78 does not. I doubt you can simply interchange most of the two harnesses.

Edited January 6, 201214 yr by cygnusx1

There was someone on this forum about a year ago (can't remember his screen name) doing the same thing (maybe in reverse, 78 in a 77) and had nothing but aggravation.

Is yours destroyed are you hoping that a full replacement will fix some problems? Many parts of the factory stock harness look like they've been "hacked" on but are actually built that way new. Most of the problems in the old harnesses are at the ends where the connections and corrosion are. Might be more worthwhile to work through the problems one by one.

ok ill give that a shot @zed only reason why im wanting a new one/better condition is so i can just build this thing from the ground up without having any issues with older parts or the ones that are in it

i just purchased a factory service manual so im giong to start hitting it with that

There are electrical differences between the 77 and the 78 such as external vs internal regulator, fuel pump contacts in the AFM, etc. so the harnesses are different.

I have a 78 under dash harness if it is of use. Just pay the shipping.

The only parts of my harness system that have deteriorated are (or were) the engine harness connectors (rotted) and a heater fan motor connector (whose spade connectors fell out). All were replaceable. The Bosch-style engine harness connectors are available on ebay ("280z injector connectors").