We are in Los Angeles for Christmas, and I immediately set to work on the vintage bike hunting aspect of suddenly being in the big city.

Later I'm going to look at an unknown Schwinn with full Campy NR. Have only one sketchy picture and very little info. It has been repainted. It's a ten speed.
I know nothing about Schwinn's, and I don't think I'm really going to develop a passion for them. Mostly I'm interested in the Campy parts but I do want to show up somewhat educated, so my question is:

How do you easily and on-the-spot pick up the clues to ID'ing a Paramount or other top tier Schwinn?