I have a 78' F350 cab and chassis dually flatbed. I fabricated a new (to original specs) bed but added 4" rails along each side with stake pockets, from that i put removable 2×10 planks for added volume inside bed. I decided that a tonneau would help keep prying eyes away so i carefully measured, made a sketch of what i wanted and took it to a local canvas/tarp fabricator that made tarps for highway rigs. One week and 150.00 later i had my custom tonneau snaps and all ready to put on with a little more measuring to install the male snap stud.*
For the X bows i went to the local marine supply and picked up 3 sets of bow cleats, 3 pieces of 1/2" thinwall conduit measured again to give a slight crown then flattened the ends to fit into the bow cleats. Works just like i planned and now we can hide our camping gear or whatever else that fits under the 7'×9'×13" storage area plus it remains there doing 70 mph, all for under 200.00
This is a pic without the oak sides yet, im in the process of sanding and paint/staining them but did have the tonneau on here for a test fit. I'll post a pic when i install the new planks.

New oak bedsides and custom tonneau coming, just need to stain/paint & install snap studs.
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