Audio Systems: Factory GM Radio, circuit city, fm stereo

Question
I have a 1978 Factory GM AM/FM Stereo.  How can I check to see if it works before installing it in my car?  Thanks.

Answer
I would go buy a new deck for 80.00 at walmart or circuit city. If you want to test that one you will have to hook it up to a 12v source and use a test speaker. If you do not have the connectors for it you can determine which is which pin at: http://www.installdr.com