Do an air dam and add pans under the engine bay and behind the rear axle. The minimal gains you're likely to see by doing a full belly pan instead of the former aren't worth it in my opinion. Use only existing holes when mounting stuff.
Roofing tar sounds promising but I still wouldn't chance it.
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He gave me a dollar. A blood-soaked dollar.
I cannot get the spot out but it's okay; It still works in the store
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