Use ZipZap tires on the rear wheels!
I'd post pics but my camera battery is dead, but here's the deal: Use the ZipZap tires on the rear wheels if you're getting light wheel-rub on your lowered bit despite having sanded out the wheel wells; they're like low-profile tires.
Another advantage is that since it's slightly affecting your 'final drive' ratio, you can accelerate a little faster (Smaller diameter tire), but not much.