My immediate response would be, yes that sounds like it would be a good idea.
I imagine that if you were really creative and bored (emphasis mostly on bored), you could mount a mirror on the cieling, and take the cushions off your couch. Then you could lie on the (cushionless) couch and look through binoculars at the mirror on the cieling to read the meter.
If you are exceeding small and your body would not make a good approximate for the cushions on your couch, you could wrap yourself in a down comforter or something.
If you are exceeding large, and your body similarly would not be a good approximate for your cushions, you could simply move the entire couch into the other room and lie on the floor.
