OK Sheldon, I managed to get some play in the truss rod. I applied the heat and some firm steady pressure and it has reluctantly let go a bit. It's not working real easily, but it probably hasn't been turned in 20 years, so can you blame it? LOL! I'll try to get some of that lubricant you suggested.
Anyway, now to adjust the height of the saddles, do you just rotate the saddles like a screw(requiring removal or at least significant loosening of the string to remove it from the saddle)? This bass has your older bridge (with the saddles that look like slotted screws) that does not anchor all the way through the bass. It has two other adjustment points forward and aft of the saddles, but I assume that is for moving the saddles forward and back. Sorry for these questions, but the bass didn't come with an original manual!