TAKE THAT, you stubborn pistol!!
Sigh.
I've probably done a bit of damage to my pistol, but it's now apart. You see, even with the recoil spring plug depressed, the guide rod was flush with the outer rim of the bushing. This meant the bushing was not going to go anywhere. Closer examination revealed that the guide rod appeared to be of two parts and was beginning to separate near the base.
Having no proper tools on hand and lacking in patience, I performed impromptu caveman surgery.
With the slide removed from the frame, I compressed the recoil rod assembly and pinned it in a compressed state with the only thing I could find that would fit: a dime. Then, I found the only thing in the apartment that would survive pounding while hopefully limiting damage - a plastic-covered free weight of the type used on dumbbells. Slide firmly in hand, I proceeded to bring it down guide-rod first onto the free weight. With authority - about half-strength, but I'm moderately in shape and 6'7". Several whacks later, the guide rod had shortened enough that (with dime removed!) I was able to swing the bushing free and remove the spring/rod.
There are very minor chips/scratches on the forward face of the barrel lug, just where it starts its first curve down from the barrel itself. The guide rod is not going back into the gun, I'm going to replace it. I probably should have used a spent 9mm brass shell instead of a dime...
What should I watch out for when I go to test fire the pistol again?
Thanks again for all your help!
Edited to add: When I first purchased this pistol, I wanted a "beater 1911" that I could use to learn the basics of how it worked without worrying much about scratching it up. Well, I literally got myself a "beater."
Time to buy some proper tools and books.