Thanks, Beav
As soon as I got myself out of "panic mode", I had the same thought. A little judicious use of the "broken axe handle between pulley and shoulder while tightening bolt" technique worked out just fine.
The really good news is that the compressor works great. I got a R134A retrofit kit and charged it up, and for the first time since I bought the car, it blows ice cold air from the vents
Any long term negatives to using the R134A vs. the R12 as originally equipped?