Scott, you may grow tired of the exhaust ending at the rear axle. I know my 70 Duster with a 458 inch stroker and 3" exhaust was so loud that it was impossible to carry on a conversation. After about 3 months, I extended my tail pipes to the rear bumper.
I 2nd this, my 3" with Flowmasters turned down before the rear axle, for me it was the reverberation from the exhaust bouncing between the body and the ground that gave me headaches after driving my car.
Love your build BTW, Would always geek out at the US Nationals looking at the Super Stock Hemi class, so many bitchin rides