I picked up what was said to be a RB-1 frame at an Oakland sale put on by a couple of frame builders making room in thier garage. It had been repainted so I don't have any decals to go by. It does have the Ritchey fork that was in this bridgestone catalog scan; https://www.sheldonbrown.com/bridgest...3/pages/25.htm .
The serial #, L521xxx, doesn't fit the dating as posted in this blog; https://www.cyclofiend.com/rbw/bstfaq.html .
Any help would be appreciated.

Many features look like RB-1 (dropouts, seat lug, braze-ons). The pump peg is normally on the headtube, but perhaps different on larger frames like this one.

Being that it came from some frame builders and that it's been repainted, I wasn't sure if maybe they had added that or if it was stock.

OK< I guess that's all we know? My main concern would be the S#.

The serial probably fits. The blog says one letter for each month, A=Jan, G=July, so L=Dec, unless they skip I (too close to 1), then Nov. The first digit is year, so 1995. The last two digits are the frame size if I recall correctly. Does that fit?

According to the article, 94 was the final year. Last 2 digits are 04 for a 62 frame. I've seen other companies that have varied thier numbers in transition, but I didn't know if that applied to Bridgestone.