1955 1st Series Chevy
January 2002 -- Roy tells us he's sold the truck!
The best way to answer the question pertaining to the differences between a 1954 Chevrolet and a 1955 first series is to read the BOWTIE BULLETIN contained in the Golden State Pickup Parts catalog. Seth Doulton explains in the BOWTIE BULLETIN, "The models that are harder to tell apart than most other Chevy years are the 1954 and 1955 first series.
The two easiest way to tell the trucks apart are the side hood emblems and the drill line. Both of these are shown in the diagrams. The emblems on the ’54 model have only 3100 on them and the emblem on the ‘55 first series was redesigned to include the name "Chevrolet" on the emblem also. 1954 was the last year for closed drive lines (torque tube) in ½ ton pickups. 1955 first series was the first year with an open drive shaft." - Seth Doulton
Attached is a picture of my 55 first series Chevy, in fact my title identifies the truck as a 1954/1955. This is an original truck, been collecting dust in my garage since 1995 and was parked in a Ford dealers garage for 12 years or so before I bought it. Both the GMC and Chevy are first series.