These are original magazine ads from the fifties; it shows that GMC spent a lot of advertising dollars to promote these trucks. One of the ads is a stepside and has some features that did not show up on production vehicles the front fender emblem looks more like a Chevy and the headlights have an extra-extended ring around them. Some of these are artists rendering and not photos.
Because of the size of these ads the file sizes are larger and will load slower. I have added the text from the ads because the scans are hard to read I felt the text is worth reading.
Just click on the text under the thumbnails to go to a bigger picture and readable text from the ads.