In the 50s, the 6189, 6190 and 6191 Streamliners descended directly from the early ‘50s Electromatic. Along with the lower-priced Clipper they were the primary models shoring up the bottom end of the Gretsch line.
That doesn’t mean they were shoddy guitars, though. The ‘55 to ‘57 Streamliners were built on the exact same body as the 6120 Chet Atkins of the era, and are effectively a single-pickup version, without the tremolo, binding or other frills.
Gretsch didn’t exactly advertise that fact, though, because Streamliners were much cheaper than the 6120 when new. They still are. With the advent of other low-priced models such as the Anniversaries and the Tennessean in ‘58, the early Streamliner’s days were numbered. It was discontinued in late 1958.
The name, however, returned in the ‘60s. The 6102 and 6103 Streamliners were primarily an attempt to take the perfectly good 6123 Monkees model and make it into something people would want to buy. In other words, they’re very close to a 6123, minus the monkey business.
There are, however, a few differences worth noting: Where the 6123 had a unique fretboard with new-classic inlays on both the treble and bass sides of the neck, the 60s Streamliners used the usual bass-side-only setup Gretsch was traditionally known for. Also, Streamliners moved the pickup and tone switches to the upper bass bout. The 6123 grouped all it’s controls on the treble side.