Technically you have a 3104 if it came from the factory as a complete truck.
The bed sides and the tailgates and the front of the bed is the same part nos.
for 55 2nd to 59. The only truck that had the side emblems that had the
actual numbers on it was the Cameo and it said 3124. (I think) All the the
just said 3100 on the side emblems. (55 to 57) I have the factory assembly
manual for a 57 if I can help any more. I also have a scanner.
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959