Autometer volt gauge installation question

[Silver83]

I know how to install the gauge, but my question is really, for guys that have installed one in their 'stangs in past, what switched source did you tap into? We're mounting in a 3-guage pod on the passenger side in my son's 84 GT Turbo. I'm trying to keep the wiring clean and short as possible so we don't end up with a bundle of extra wires running under the dash. The other two gauges in the dash are a mechanical oil pressure and mechanical temp sensor. We're not deleting the factory gauges, they still work. Just thought I'd ask instead of re-inventing the wheel if someone else already accomplished this.

[gr79]

The switched radio power wire works for me.
Is close to where the gauge is mounted.
This is voltage available at the dash vs somewhere else.
Tap into a wire you wish to monitor for voltage.