Bad chain tool, bad
Finally got the cranks on, the pedals on, the new 17 tooth cog on the old wheel that I re-tensioned and trued (well, partially trued at least), only to put the chain on with a broken chain tool. (I didn’t realize it was broken). So one of the bushings became bent, and on my ride home, I popped the chain. Tried to use alternate links to fix it, but they stuck (and ended up with only slightly bent bushings). So a new chain it is for me, unfortunately.