I thought I would add to this posting, since we got something of a little bit of weather that wasn't too hot and not too cold - which motivated me to go back and take another look at the non-working radio, especially since I thought through and eliminated a few more possibilities that has narrowed down the problem.
Through some "fiddling around", I've ascertained that the cassette tape deck is working fine - except for the lack any sound being produced. The fact that the lights on the equalizer are not lit, lead me to take a look at the equalizer unit (which is located underneath the lift-up rear seat). After disconnecting the two modular plugs and removing the unit, I check the continuity on the unit - which looked good. I also tested what appeared to be the two power leads (with
the ignition in the Accessory position) - but no voltage registered. So, there appears to only be an upstream power issue, that is preventing the equalizer from functioning - although I couldn't locate anything in the user's manual that seemed to link a specific fuse to the equalizer. Other than running a pair of positive and negative power wires back to equalizer, and splicing them into the dead power inputs - what other options do I have?