Thanks all!
Going to pepper a few more questions here:
1) how can you tell the frame is a 21" vs. a 23' from photos?
2) Pretty happy to use 27 1/8 if I can find a bike with a good set of rims, but any luck moving to 700c (maybe with 35-38c?) wheels in these if not? Fork and rear look reasonably spacious.
Cheers!