key goes in, radio powers up

Wow, lots to look at in the short time since I posted this. Thanks to all who responded. I crawled under to start tracing wires not thinking about the head cold I have had all week and after about 3 minutes felt like the top of my head was ready to pop. So will have to look at it next week. Did determine that it was only with the key in the ignition. Didn't matter if door was open or closed or lights were on. Everything else seems to work as expected but I see where your going with that though, and will give it some thought this weekend. Did they have chimes for key in ignition in 70...I need to look at the wiring diagrams WJAJR linked me to. As long as no one thinks I got a short/fire hazard someplace I can live with it for a bit.
Thanks again guys!