yeah of course!

2- 2x10s at 72"L spaced about 17" from the sidewalls3- 2x4s snug into notches on the 2x10- the two longer braces are 56" and the middle brace (centered at 36" on the 2x10) is 43" across 2- 15/32x4x8 sanded plywood- ripped them at 72Lx28W so the seam runs down the middle of the bed. I had to make a small cutout at the bottom left and bottom right of the plywood to fit around the tailgate, about 2x3"

I went back and installed 4 L brackets on the middle brace, it was okay with the plywood in but would move around a lot over bumps etc.

This is the mattress i got, it folds into thirds so i can stow it to the side when traveling, it's also shorter than a standard full @ 73" so it fits perfectly