'Partial Panel', why not 'NO Panel'
I was just looking at a cold-war jet that had most of its instruments removed, and felt that was a pity... But, at a push, just how un-flyable is an aircraft with no instruments?
Whilst under instruction in a glider, my instructor would tell me to keep my eyes 'outside the cockpit'. I could even trim by feel of the position of the trim lever. Admittedly the air-sound on the Perspex, was a bit of a give-away for an airspeed check, and the position of the nose on the horizon was another good indication.
Maybe instead of Partial-Panel, a full No-Panel circuit could be flown in an SEP airplane. It would rely on you knowing the settings by feel, and the engine revs by sound. Also to pay attention to the trim index, instead of just adding a few nobbles... (I realise some gliders have spring loaded trimmers, which could pose more of a problem.)