95 harness into 96
 

So question for all of you. I recently picked up a rusty 95 miata that has super clean body panels and a blown motor. Now my question lies in the wiring. Can I swap the entire 95 wiring harness over into my 96 miata. Before you are quick to write this off yes I know 95 is obd1 and 96 is obd2. This is where things get more complicated. I am going to be running a 2002 motor on an MS3 ecu. I know the vvt motors can be dropped into any NA miata with some wiring tweaks. The harness in the 95 parts car is very clean and looks unmolested. The wiring harness in my 96 has melted wires and looks like a bunch of rats started chewing some of the wires from past people trying to put sound systems and other gadgets in. I know they greatly changed the ecus and harnesses between 95 and 96 and if I was running a stock ecu and a normal engine I wouldn't bother asking but seeing as this car is becoming a frankenstein I was hoping someone would have a better idea about this than I would. Thank you for any input!
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Does your 96 have anything your 95 doesn't, e.g. adjustable coilovers, roll bar, etc.? It might be easier to swap all that (plus the motor) over to the 95 than it would be to swap harness.

The 96 miata doesn't have any rust the previous owner had it all repaired. The 95 has all the typical miata rust on the rockers and even rusted through the trunk floor. That is the only reason I'm considering swapping the harness is to keep the clean shell. But I would swap the whole harness, dash engine tail lights. Every piece of wiring would be changed. The harness in the 96 as I said earlier is in very poor condition and the 95 harness is pristine.

It is doable, just would be super annoying. As long as your don't have to get through emissions later on I don't see any problem with doing it. Not sure if gauge cluster would have to be swapped over also.

To do it properly, you will need to remove the entire interior, including the dashboard, HVAC, and carpets. Ballpark 20hrs of labor. I think it's easier to just find a clean, rust-free donor and build into that car.

I'm not worried about the work. The 96 Chassis is already completely bare. The carpet was moldy and the heater core was leaking so it already stripped out clean. The 95 was bought as a part out so it will also be stripped to a completely bare frame. I was more concerned about essentially turning my 96 shell into a 95 car. But if it is doable and just think of it like a 95 instead of a 96 I'm okay with that.

Then yes it is doable. When getting a MS3 you would get one for the 95 harness.

That is such a relief. I really didn't want to have to try and repair this harness. Thank you so much guys. I will be swapping this harness into my 96 then.