The truck for today comes from craftymore's collection and is the Yatming '67 GMC L Series.
This model was introduced in 1960 as an L model designation but was really more referred to as the T series "Tilt cab". It ranges from T5500-9500 series with the 9500 sitting much higher. It ran well into the 80's with very little change outwardly.
For more information and pictures of the real truck please see: Hankstruckforum.com
From info pieced together, the L series began production in 1960 and ran through the 1980s. If anyone has any more accurate info, please post a reply.