The Stovebolt Site Forums The Shop Area Paint and Body Shop Advanced Design Box Assembly

Next week we are going to do a trail assembly and installation of the box on a '49 3100. We think we have all the pieces. The reason we want to do a trial is that there are still some parts that need to be final welded into place. Plus there has been a lot of repair work done on the sides and front panel. We want to make sure everything fits as expected before final primer and paint.

Any advice or guidance about the assembly is appreciated!

Here are a few questions we have.

1) What size and style hardware was used at the various box assembly points? For example the front panel to crossmember, front corners of the front panel to the sides, and the rear of the sides to the rear crossmember. I cannot fit a 5/16" drill bit into any of the holes and slots but I find it hard to believe that the box was held together with 1/4" hardware.

2) How thick are the boards for the bed? I think they are 3/4". We have not bought the bed kit yet so we want to duplicate that thickness where the mounting blots go through the crossmember and frame.

3) What is the orientation of the angle strips that are welded to the sides of the box. Does the leg that attaches to the box go up or down? Does the horizontal leg rest on top of the cross members or does it butt against the ends? Or does it rest on the bed boards?

Thanks for the help! And enjoy the holidays!

There is a couple of Tech Tips that may answer some of your questions. Bed Mounts 1/2 Ton Advance Design and another on Rebuilding Wooden Beds.

Hi Phil,

Thanks for those links. I agree that are great sources of information for mounting the box and installing he bed. We will be very happy when we get to that stage!

I did find a source that explains how to mount the angles along the side. So I think we have that covered.

Still trying to determine what size hardware is used to bolt the box together.

The front panel to front cross-sill and front panel to bedside bolts were 1/4". Since there are quite a few of them at each joint, 1/4" bolts are plenty strong enough.
The rear cross-sill to bedside bolts were 5/16. Since there are only 4 of them per corner at the bottom of the stake pockets, GM upsized them a bit.Mar-K's catalog shows them as indented hex head bolts with an integral washer on the head for the rear, if you want to stay with the original style. Their catalog # for zinc plated bolts is 100577 for your truck if you don't already have them.

Hi Kevin,

Thank you very much. That really helps me understand what I was observing.

And thanks for the tip about using the Mar-K catalog as a reference.

Here is some detail on the boards, thickness and dimensions.
A=3/4" (board thickness) B=1/4" C=1/4" D=1/2" E=1/8"
https://www.flickr.com/photos/advance-design_parts_co/9689547056/in/album-72157631884205225/

We were able to do a successful mock-up on the box on the frame earlier this week. It really helped us properly locate the angles that are welded to the sides of the box.

Thanks for the help.