I take Marc's point that you can dive from PSC (that holds for all boats I think).
Just to clarify, of the four boats I've lived on since 1973, the PSC is most challenging due to low large-space storage and high freeboard. I'm as interested as you are to learn how to store the tanks. It is intriguing to consider arrangements on the lifeline but with spare fuel
and other things taking space there, that's limited too.
Inflatables are the easiest tending dingy for diving. I'd get into the zodiac and hand the tanks up. I'm sure you realize what dropping a tank can do to your deck so be careful with that.
Good luck with this.