How to install tach

[gumby]

I have a tach that came with a recoil I bought 12 years ago.  I went to install it last night and was really confused.  I have the hole in the dash for it but no loose wires or connectors on the sleds wire harness to hook into.

The back of the tach has 4 wires coming out of it.  I found 1 yellow wire on the sleds harness that comes out of a connector and then is just electrical taped off.  All the other wires are connected to something.

What am I missing?

[oldscorpman]

here is the 78 wire diagram from my service manual. hope this helps.

rick

[gumby]

Great, thanks!