Dial light wire (orange) for this AM Radio?

I believe that on "your radio," (by model # is definitely a 1964) the orange wire is for the light. The red wire is for power, you have the speaker wires identified right. The black wire attached to the outside of the radio chassis, might be something someone added. The black wire coming out of chassis, should be the radio ground. I tested my radio on the bench using a 12V power supply, and the wiring configuration I described. Red to the positive side of power supply (battery) black from the chassis to the negative side of the power source and that stray wire on the outside of the chassis, you might try running to the speaker frame. (not necessary, but what the heck) The orange wire would receive it's power from the headlight switch and the radio on/off control. The wires that attach to your connector (with the red and orange) should both supply power to the radio. The red should be hot with the ignition on and the orange, hot with the headlights on. I would recommend having an antenna attached. It should play.
I'm open to correction on my recommendation here.
Norm