Factory Tach

[Blazin]

I have the gages out of my 79 K30 to replace the speedo cable and make wiring my sander, back up lights, and beacon easier too. When I had the motor out last week I noticed a brown wire that came from inside the cab and terminated in the general area of the distributor with a plug that matches up to the tach plug in the cap. I have had more than a few motors out of chevy trucks over the years and don't remember this wire. It along with the wire that normally plugs in to the battery position on the cap was plugged into another harness but all it did was go to a small plug on the RH valve cover and that had wires out of it that plugged into the dist cap and a ground under the plug on the valve cover. I assumed it was what was left of some emissions and deleted it. This same wire comes up behind the gages along with a ground from the ground bar on the e brake bracket and a key on power feed from the fuse block. Is this the plug for a factory tach?  

[roundedline]

I got confused reading that, can you take a picture?  Is this in your 79 K30?
All the tach dashes I have had the pigtail goes from the back of the gauge through the firewall and into the cap.

Chris Lucas
www.73-87chevytrucks.com
www.captkaoscustoms.com
Project Su
Jimmy 2WD Project

[Blazin]

It is in my 79 K30 but only the brown wire runs to the distributor. Sorry for the long confusing post. I dug up a factory tach gage cluster out of my shed and looked at it, the factory tach wires are separate from the main gage harness. I was going to put it in but the 79 is elec. oil pressure gage and the tach gage cluster is mechanical. I ended up putting a Sun mini tach in and plugging into the factory tach plug.