Forge04 that has been discussed many times in several threads since we first learned of the death of the AV and 2013 was going to be the last year. In addition to what you mentioned you would need to make the sail panel supports and numerous other parts to complete the conversion from a Suburban. We all know it physically can be done but the question is could it be done on a profitable level that GM would be comfortable making a limited production truck that may lead to owner complaints of faded cladding and water leaks.........
I don't know if it was a consideration with the release of the High Country Silverado but GM could make more money probably with that truck since it looks like you use all parts from standard production Silverado and just drop in a bed package to simulate an AV. That way if for some reason that option package doesn't sell they can keep on making standard Silverados without specialized limited production parts.