It would seem to me that a drop spindle does nothing to the steering and suspension geometry. That's why I chose that method. Lowering the back changes your driveline angle a little but not much else. All you have really done is lower the center of gravity a little, I don't know a lot about stovebolts but I know a little about towing. A modern 1 ton dually doesn't even know a 40' fifth wheel is back there.
And that's what I'm hoping will make this a success. As far as driveline/chassis go, I'm not doing anything new or radical. There will be a ton of changes, but most of them will be as simple as a spindle change. Air rides have been done elsewhere, and the challenges are well known. So I'm pretty sure I have this. But I will look forward to hearing from everyone.