72 GMC CUSTOM 1500 Dashlights Problem

[slowboy]

I replaced the dash cover on my 1972 GMC P/U.

Since the dash light bulbs needed replacing and I had removed the dash, I replaced all of the bulbs...
plus I went ahead and put in a new headlight switch as well.

After getting the dash cover and headlight switch in, I installed the dash bezel with gauges. Once I had it installed I connected the battery and tried the dash lights out.

I pulled the knob out for the lights and...no dash lights, although all exterior lights are working.

I turned the knob back and forth and the only light that came on was the interior light.

After twisting the knob for the headlight switch back-and-forth several times I finally got the dash lights to come on, but just the upper ones. The bottom row, alt-temp-oil lights at the bottom of the dash didn't come on.

Plus the left turn signal doesn't work, no light, although the right turn signal does.

Anybody willing to help me figure this out please?

I'm going to take my test light and check the connectors for power at the headlight switch and the connector on the wiring harness for the gauges.

What I'd like to know is which wires should show power with the ignition switch off and which should show power with the ignition switch on.

As always, much love and respect to you all and all help is deeply appreciated!

Keith
(slowboy)