Problem solved! I purchased a Sullivan Dynatron high torque starter motor.

Sullivan Products

I placed the Sullivan against the spinner, pressed the switch, and the motor would turn over at about a speed I would judge to be significantly over idle. Far more than enough to get the fuel flowing.

My OS .91FX is mounted inverted, with the fuel tank very slightly above the carb. This results in a very slow drip of glow fuel from the carb when the needle valve is open. The rate is about 1 drip every 6 to 10 seconds. Since the drip is dropping OUT of the carb, and not INTO the carb (inverted), I figure that the engine is practically self priming. The only problem is that a simple one time flip of the prop is not enough suction to pull the fuel INTO (up) the carb.