There may be a 2nd set of bottle bosses under the down tube. That was a pretty common location. in the early 1980s, when the seat tube was the preferred pump location. This bicycle looks circa 1983-1984. Or it may have only a single set of bosses to hit a price point, as that tubeset decal looks like an economical Tange 900/1000. I'd appreciate the serial number for my database. TIA.