I'm sorry, but that rear wheel well gap is absolutely horrifying. You need to start working on a car length skirt set-up like the ones Basjoos and Aerohead have on their car/truck
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Aerospace Controls Engineer.
Currently driving a mostly stock 2014 Mitsubishi Mirage DE hatchback.
Do you have a list of your mods , also did you ever think of lowering your truck if you didnt do it a bit already , mine has the same I beam front end and wondering how much you can go with out major work was thinking about lowering the rear of mine about 2 inches then going with a one inch larger tire and netting about one inch drop and better drop in the revs without messing with the front end, interested to see if you get any gain with the covers, I drive most at around 53 mph so wondering if any use with these or strictly a 65 mph gain .