Replace 1976 with 2004 wiring harness?

[Luislang]

Hi friends,
For the past 3 years, I've been building a 930 3.3 using a corrosion-free genuine barn find rolling chassis. 2 years ago I found a nearly complete decade-ago disassembled 3.3 Turbo motor on craigslist for 4.8k
Yes Victoria - Santa is real.
Included with the zillion boxes of parts was a complete wiring harness from a 1983/4 model.
Since the 3.3 has lot of stuff not found in 1978, I am thinking of replacing the old wiring harness. Is there anybody amongst my respected Porscherati that have done this. Do you have any info on integrating original components into the new harness.
Any notes, documents, wiring diagrams I can get from you?
Am I committing myself to another 10 years of haplessly trying to figure out which wire goes where?
Thank you in advance!
Ray

[Luislang]

Correction- 1976 model chassis, 1983 engine

[Flat6pac]

1983 turbo will be European/ROW so there is no lambda controller.
The harness on the engine is for starting and dashboard information.
By 1976 the dashboard for the 911 is the same style as 1983.
Differences would be in the pressure and temperature gauge, tach wiring for the 6 prong CD.
Pressure boost gauge wire would have to be run separately.
I know the 14 prong connector on the turbo engine harness is full but chassis side isn't on the 76 or 83 SC but can't think of the wiring differences. The turbo motor is made to run on after shut off to burn fuel under pressure.
Bruce

[Luislang]

Thank you, Bruce.
That helps a lot already. Any references to wiring diagrams I can access to compare?
Thanks,
Ray

[Flat6pac]

If you have the factory schematics you could compare but they don't layout like each other.
Meter your engine harness the figure it against the 76 schematics. I know there is a couple extra wires in the turbo harness BUT are they necessary ?
Bruce