I actually did a 21" magna flow and dumped it infrot of the axle. Turned the tip 45deg to prevent the note from bouncing off the ground. Sounds nice in the cab. Only a slight bit of drone at ~2200rpm going up hills. nice sounding on the freeway.
Could someone contact Millersss? looking to see if he still has the pics from his radio swap. Needing to figure out which side of the circuit is positive.