It all depends on how much money you want to spend on your aero mods. The front is not a big deal, i wouldn't do too much cutting/welding to make the wedge shape you had in the 3rd post , you can just add a piece of plexiglass from the tip of the front bumper to do the tip of the hood so you don't have that "scoop" at the front but the biggest mods should be done to the underbody and back. Maybe make a adjustable kammback and do some tests to see what works best. I would cover both the front and rear wheels and add lawn edging all around the car
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