Hi All. I would like to bench test a 1965 AM/FM Radio (Service Model 7289772). Before connecting the wires I want to make sure I don't get smoke coming out of the radio. I believe the blue wire with red plastic tip coming out the side is the 12 volt power plug?  In the back is a plug with a Black/Yellow a Green and a Black/Green wire. Can anyone help me as to which color wire is the power, ground, and speaker wires. Thanks Much!

Please excuse the typo in the title. It's a 1965 NOT 1956 radio.  

OK, since I didn't get any replies I decided to bench test it and took a guess. I hooked the blue wire to the 12v power, black & yellow to GROUND, green to one speaker wire and the black & green to the other speaker, plugged in the antenna and hit the power switch. BOOM, BIG CLOUDS OF SMOKE!! ..........Just kidding. What I got was beautiful music on AM and FM.