Hi Jon,
Just spoke with Mar-K Quality Parts. They said it would be fine to pass on information from their bed parts assembly guide. I bought new bed strips from them and cut my own bed wood just a while ago. With the new strips they included lots of helpfull information. The old wood was long gone on my truck. Would recommend this vendor to anyone.
Quoting... Attach the cross sills to the 5/16" angle strip bolts approximately 2-1/2", 26-11/16" and 53-11/16" respectively from the front bed panel.
The second, fourth, and sixth bed strip holes should line up with the cross sills.
The first cross sill at the front is the first bed-to-frame hole location. Mark the bottom of the second boards from each side through the 1/2" diameter cross sill holes that are 36-5/8" apart from center of hole to center of hole.
The second bed-to-frame bolt location is in the third cross sill counting back from the front bed panel. Mark the bottom of the outer wood boards through the 1/2" diameter cross sill holes that are 44-1/4" apart from center of hole to center of hole. The second cross sill does not have a bed-to-frame bolt.
The third bed-to-frame bolt location does not pass through a cross sill. There are two brackets attached to the rear cross sill. These large brackets should fit against the bottom of the wood boards.
Mark the bottom of the wood boards through the big brackets. The spacing of the bracket holes in reference to each other should be 44-1/4" apart from center of the hole to the center of the other hole. These marks should be 73-1/4" back from the front of the wood.
Make reference as to which end of each board is at the front of the bed. Remove the bed strips, cross sills and wood boards. The bottom side of these boards should now have 1/2" diameter holes marked on them. Drill a 1/8" diameter pilot hole through the center of these marks completely through the boards.
On the top surface of the boards, measure toward the front of each board 3/16" from each pilot hole and mark the boards for the countersink.
Using a 1-9/16" Forstner bit, a drill press if available, or a hand drill, countersink each location approximately 1/8" to 5/32" deep.
From the top surface, drill through the 1/8" pilot holes with a 1/2" drill bit to complete the bed-to-frame holes.
