Wiring new gauges

[69dodge383]

I got my car going but think I need to wire my gauges differently, or more correctly. I put 6 new gauges in my car 2 1/16" diameter all are electric. 2 are A/F readouts, digital oil, water, volt. digital tach with light from summit.

When I start the car they work and after a few minutes of running they starting dying out, either not showing number that make sense or show a zero. I notice that my volt level never goes higher than 12v when the car is running.

I just wired these up like so, found the 12v key on source, cut the wire, and split it into two sections, i wire went to the MSD box for 12v, the other goes to all 6 gauges and the switch to my electric exhaust cutouts.

I dont know if I have too many wires on one wire or if that even matters, I just know these gauges are not working like they should. I have heard that if they dont get full power they will not work/read right.

If anyone out there has any tips, I am all ears.

[myk]

I don't know about diagnosing your problem, but how did you mount them?  Did you install them into the dash, or did you have custom dash panel or something?  Pictures if you can!