Radio troubleshooting/options

[slotard]

73 C20, idiot lights rather than gauges (not sure if that matters). A decent mess of wires under the dash.

The radio doesn't seem to do anything at all and I'm trying to figure out what troubleshooting steps to take. Previous Owner doesn't remember it working but isn't sure he tried.

If I get a new one I'd rather not have to hack up the dash. Aux in would be nice. Sound quality isn't all that important.

Thanks for any help.