That tail, stop, and turn light is an Arrow Model 3. I have a good one and several for parts. The glass lens is hard to find in one piece, and the few I've found were very expensive.
https://picasaweb.google.com/lh/photo/RgYJv2FYaERg4HpqyjVikdMTjNZETYmyPJy0liipFm0?feat=directlink

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-