I finally got the new sub box installed and complete. I also installed the Extang RT Tonnaeu cover. I was worried about the quality and how sturdy it might be but after installing it I am very impressed with this soft cover.

I took it to the car was today and it only leaked slightly where there is a gap between the tailgate and the body of the truck. The cover also came with thier tailgate seal for free which should fix that problem.

I purchased the cover from AutoAnything for $377 - free shipping - free tailgagte seal.