That's actually been done (check the Kingman section).
This frame came with a vert AGD ASA installe just as you describe (filed off the "nub", drilled and tapped the lower, blockier part of the guard, drilled the upper part and used a nut). I took off the hardline the PO had because it didn't seat right with my powerfeed body but I'll probably reprise the system using macro/steel. Just need a duckbill that drops the tank down straight instead of forwards... to Bacci's!
Originally Posted by Hooligan
I found a way to make a sabot for a twinkie. The other tanks smell like banana cream filling now.