I'll agree with the others and say that the bedcover will probably yeild the best results...if it doesn't compromise the usefullness of your truck.
I think my rubber belting front spoiler(pics in my album) smoothed out my front bumper and helped a little, but I haven't done any a/b/a testing to prove for sure.
I am seriously contemplating lowering my truck a little when it comes time for new tires and an alignment. The torsion bar crank on the front doesn't seem too bad from what I've read about it, so long as you get an alignment done also. Lowering the rear a little will involve a different set of springs or some type of lowering blocks...I haven't done enough reading up on this yet.
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