Thanks for the link Garry. Much appreciated. After hearing some advice from a kind soul over on photo.net, I decided to just bite the bullet and grab a screwdiver and hammer and "tap" the top off. After a few ticks here and there (and some scuff marks), it popped right off. Whew!
Of course, after replacing the bulb (I'd found a source for the correct bulbs earlier), there I'm not seeing any light, so I'm now assuming the wiring is bad. I noticed when I got the unit that the wire coming down the pole had no ground, just one hot, so perhaps there's some disconnect or other electrical situation. I guess it's time to hit home depot for some new electics.
Thanks again,
b.