Wiriing application ???

[pookie]

I am trying to install a new tach since my doesn't work. But I have a few questions. I have never been able to find the right wire that is supposed to run to the tach in the engine compartment of my car. To say my wiring back there is messed up is an understatement. My question, is there a way to run a wire from the dash to the MSD box in the rear compartment? And what is the best way to run a wire from the back of the tach to the MSD box? If anyone has any ideas please let me know.

Thanks in advance
Ryan

[pookie]

Ok so no one can help a brother out. How about this one, can anyone tell me where the violet and purple wire that runs from the tach, come out in the engine compartment? Is it in the main wiring harness or does it come out of the driver side rear fender?
Also some pics of the old and the new to show what I am trying to do.
[img]
http://forums.pelicanparts.com/uploads3/DSC006761096058624.jpg[/img]

old tach



new tach

[jpnovak]

Teh black/purple wire will come out in one of two places, both are on the rear electrical panel. The wire will enter the engine bay inside the main wiring loom. It will then pass through the first 14 pin connector under the CDI box. On later cars it will exit here and go to the 6 pin connector on the CDI. On earlier cars (like yours) it should go through the second 14 pin connector into the engine wiring harness. It should then exit near the coil and down to the dist/points. There will also be a black signal wire that runs from the points to the CDI in a similar manner.

Hope this helps. you can always look for a 12V squarewave (~30% duty cycle at idle) coming from the dist signal wire using a MM.