If you have not visited
www.Mar-K.com you really should.
At the top you can select your truck year and model to visit their parts catalog for that truck's bed. Lots of good exploded drawings and info about what parts & quantities go on that bed.
A few months ago, I ordered cross sills, angles and strips for my 53. They included detailed assembly instructions for an entire 53 bed with the parts, including photos and measurements.
I bet Mar-K has similar instructions for your truck.
