Hey folks,
I just built a PARTIAL tonneau for my pickup truck.
It covers the back two-thirds of the truck. The idea is that if air is hitting the tailgate, it's coming in towards the back.
There should be a lower pressure area right behind the cab, where the bed isn't covered - so air really shouldn't be pushing in there.
I can also still use the front part of the bed to just throw stuff in there, or have a tool box, or something that would stick up a little too far to be under cover.
Here are some photos.
I will let you know how my next tank of gas turns out.