POLL-Paint or undercoat?

This is DynaMat.

If it's noise your concerned about, use this stuff.
http://www.ebay.com.au/itm/Dynamat-10455-Xtreme-Bulk-Pack-9-Sheet-Bulk-Pack-/281151678664

I'm pretty sure summit over there in the U.S sells it as well.
Id just use a good rust proofer like POR15 and then dynamat and then lay your underlay/carpet.

Me personally , I like it loud, Hot & Fast.:burnout: