Well…I futzed around a bit, and basically did this:
https://www.ads-software.com/support/topic/21984?replies=5
More or less just renamed all the b2 databases to their wp counterparts, and ran the b2-2-wp script. Seems to be working so far.
Now to upgrade the rest to 2.0.0 and we’ll be dandy. It’s on .72 now. Hey, it’s a big step for me!