Aftermarket Volt gauge wiring

[rocketBox]

Hey everyone - I have a 70 F250 - just finished a modern radio install on the truck, oil pressure gauge and capillary line install, water temp gauge install, and got the gauge cluster lights working to the ignition switched power... only one gauge left to wire in, the volt gauge. My question is where do i wire this thing up to? I have a ground feed that i can connect the negative to, but i'm not sure where the positive wire should be connected to. This may seem like a dumb question given all the other work i've done, but i haven't ever had to wire one of these volt gauges in before. Thanks!

[Ohiotinkerer]

The hot lead is hooked to a keyed/fused power source - something that is only hot when the key is on. Its been a while since I've done one but if memory serves me correctly I wired it into the 12v lead on the ignition switch.....

[rocketBox]

huh - that's it? seems easy enough... damn, i should have just spliced the power and ground going to the lights on the gauge and wired it in then. Thanks!

[colnago]

i should have just spliced the power and ground going to the lights on the gauge and wired it in then.

You don't want to do that, or you'll only get voltage when the light to the gauges are on. Maybe splice it into the keyed power going to the radio, if it doesn't draw a lot of current, just because that's a fairly easy wire to access.

Joseph