the other day I was asked if my '57 3100 had originally run a V8 (it's currently a straight 6). the guy referred to the hood emblem- see below link
http://i858.photobucket.com/albums/ab145/BagdadChevy/DSC03631.jpg
I looked into it some (through catalog sites) and found that there were different emblems for '56 based on engine, but I only see the one hood emblem (called a V8 hood emblem) available for the '57's.
I'm pretty darn sure this 6 cyl is the original with the truck- can anyone confirm?

http://photobucket.com/1957BagdadChevy