Re: can you run drive without a prop installed
With no prop on, out of the water (e.g., trailered, on muffs) it would be no different engine response in gear than it is if you are revving the engine while in neutral (except that the empty prop shaft is also now turning)...(although you should always be careful with throttle chops while on muffs and operate the engine with the recommended RPM from the service bulletin for operating on muffs to prevent water intrusion).
I typically don't engage my fwd or rev gear while on muffs anyway (there are other ways to test your shifter with the engine off, out of the water). But, as said before, it would be safer if you do want to go in gear (for whatever reason) without the prop on it.