Clay, if you run a front Air Dam (legal in Your class) You probably won't be getting that much air under the car.
I I was building a new car and could afford it, I would powdercoat EVERYTHING, INCLUDING THE COMPLETE BODY, CHASSIS, TIN WORK, BRACKETS, et al. Everything but the nuts and bolts. I have had problems on My trailer with bed liner getting moisture underneath the coating on the axles,etc.
On My existing car I only did the chassis and suspension and it's the only thing that has held up for twenty plus years.
"One Run" Bob, out...................................