Back in 2021, I bought a 1989 Schwinn Circuit. It is a 22" (55-56cm) frame. I bought it because I was fascinate by both the frame itself (Candyapple red, Columbus main tubes, with chrome Tange Aero stays and fork) and the groupset (Shimano's Sante). It came with all the original parts, except for ONE of the black rubber nubs that go into the pivot bolts on the single-pivot brakes. I normally ride larger frames, 57-59cm, so it took a long seatpost and a 130mm stem to make it fit. Mostly.
The thing is, the bars are about 2 m lower than any of my other bikes, and I found that after long rides on it, especially if I do much riding in the drops, I get some lower back pain.
SO, I found a 23" (58cm) frame on Ebay. Same year, same color, etc. But this time, in my size. No fork, though, and obviously the fork from the 22" frame wouldn't fit. SO, I found a 24" 1988 Circuit frame and fork. That frame is a bit rough. Lots of rust spots on the top tube, etc. BUT the chrome fork will clean up nicely!
Here's my plan: Get the fork from the 24" cut down and threaded to fit the 23" frame, then swap all the components from the 22" frame onto the 23", recreating a completely authentic, but not original, 1989 Circuit in my size. And a really nice 22" frame.