Proposing this to be a 1956 Minute Man "B" based on other watches in the DB (https://mybulova.com/watches/1957-minute-man-11063). Picked up on the auction site for the paltry sum of $19.43 shipped, amazing. Running about +120sec/d. Case and dial are in REALLY nice shape, the glass crystal, eh, not so much. I might try a polish with cerium oxide before replacing what looks to be the original crystal just for fun. The G-S catalog 60 lists the Minute Man B crystal as the CMT358-13 at the exact dimensions I get with my caliper. L6 on case back, L6 on movement.