I play alot of regular upright, and had a Carruthers Sub-1 as a fretless. It had the screw on upper bout thing that allowed you to hold it/stand with it like an upright. That is a mod that might be done to your Classico---maybe contact John Carruthers and inquire about this. The general rule for upright is too keep your inside leg behind the bass--this will help you have a straight fretting wrist. Personally, I would play the Classico on its stand, sitting or maybe standing, so I could get my inside leg behind it, and not have to try to balance it.