Between the GMC T-14, T-16 and T-18, {1/2 ton, 1 ton and 1 1/2 ton) they are all different.  I believe the Chevrolet would be the same.

I should have put more detail into my question. Other than the brackets, can I simply weld the rear sections of pickup running boards to the rear of the big truck boards to make them the proper length or is the width and height different where they meet the front fender.  Some of the diamonds are worn through on my pickup running boards and I have access to rust free big truck boards. If the diamond pattern and spacing on the surface is the same, I can always use the big truck boards to make patch panels to repair my existing pickup boards.  I’m looking for alternatives to doing a weld repair on each diamond. It’s a two hour drive to see the big truck boards that I want to avoid if they are not even suitable for patches.  Thanks,  Mike

Mike, The front fenders are the same for all Chevy trucks in 1936 so you can count on the bolt-up situation to work. I would imagine that the diamond pattern would have the same spacing, beginning at the front but this is speculation on my part.

My 1936 truck is a 1-1/2 ton model with short boards. For a very reasonable fee, I would be happy to share pictures and measurements to help you answer your question. Do you still have my number?

Mike

After some careful measuring and a discussion with 35Mike, I bought the big truck running boards.  As mentioned, the fender end is the same as the pickup boards so they will bolt up.   In addition, the rest of the big truck board profile replicates the pickup board except for the last 2” or so.  In summary, it appears big truck boards can be converted to pickup boards  by extending them about 19” with the rear portion of the pickup board.  Also the spacing on surface diamond pattern is the same so depending on where you cut, making patch panels is also an option.  I know this sounds like a lot of work but with scarcity of pickup running boards it’s an alternative.  Mike