Well, I went ahead and installed the used bridge pickup yesterday afternoon/night. It's crazy bright sounding.... have to turn the tone down almost all the way or it's shrill - the old one (now dead) seemed to have a much more balanced tone. Why should that be?
I just checked, and both pickups in the guitar, now, attract, rather than repelling (the old dead one attracts, too). Alas, there seems to be some problem when using the bridge and neck pickups together - they have very low output together.