I'm seeing the same problem with 2-1/4 blocks with an addition of the thickness of the rubber spacer pushes the rear sill mount about 3/8" in the air. This does not seem right. Any body have a clue as to why the blocks are cut too thick. I do not want to torque the bed down and stress the side bed panels.
Just for the record this is a 36K original miler with original sheet metal never hit and the frame is straight as a pin too.
Bluemeane might be right the spacer blocks and rubber spacer should equal 2-1/8" combined to eliminate the gap at the rear sill.
Attachments
bed.mount1.jpg (69.18 KB, 111 downloads)
bedmount2.jpg (36.4 KB, 113 downloads)
bedmount3.jpg (45.25 KB, 104 downloads)

Last edited by sstock; 10/26/2017 6:04 AM.
1953 Chevrolet 3100
261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done
In the DITY Gallery
Video of the 261 running

1964 GMC 1000
305 Big Block V6, sm420, the next cab off restoration