[dscott]

Rz, It sounds like the gauge is hooked up properly. You won't get a voltage reading from the sender because you are changing the resistance of ground. I still think you have a mismatch of the gauge and sender.

The alternator circuit needs to have the idiot light in the dash harness hooked up. This completes the charging circuit. It won't show a charge unless you have the dash harness plugged in.

The horns need 2 wires to them # 154 and a ground to chassis. Make sure you have a fuse in the fuse box for the horn.

Don