Recently a new G506 buddy and I noticed yet another difference between the early YP model Chevy and the later "N" series trucks. The bed mounting system on the early truck (in this case both are Hercules Dump models) is markedly different. On early trucks, the bed is bolted directly onto the top frame rail with (5) 7/16 inch bolts per side. The N-series truck beds are mounted with (4) U-bolts, and a rear bracket on each side. YP model truck frames lack the rear bracket, and also lack the mounting holes. One more method to ID a Chevy frame vintage.
Bed mounting system on N-series G506. Notice the rear mounting bracket (circled), and the rear U-bolt.
Bed mounting system on early YP model G506. Note the simple bolt attachement on the top frame rail (circled), and lack of U-bolts or rear mounting bracket. Early frames are also not provisioned with the rivet holes for the rear bracket.
If anyone has a YP model truck with different bed configurations, I would be interested in seeing the mounting system.
Paul