Denny,
Here are three pages from the 47-55 Factory Assembly Manual - diagrams of the dual-action fuel pumps on various sizes of trucks:
Sheet 18.00 RPO 340 Sheet 18.00 RPO 340 Sheet 18.00 RPO 340 Here is my 54 233 with home-made plumbing of a dual-action fuel pump. I could not make out the the routing of the tubes on the 3000 series trucks, so I put one between the water pomp and water outlet .
