Rob,

An H-16 uses a pin in a link that keeps the mast under control. I would think that Nacra had some similar device but I don't know much about them. There was a system on the market that allowed you to lengthen one shroud to more easily right an H-16. Part of that system included a cable that somehow kept the mast from coming out of its socket when the shroud was loose. There may be some way to adapt that concept to control your mast.

I can't take credit for the jib halyard idea for holding the mast up. I read that in an old Hobie Hotline years ago. I have been raising the mast solo for so long that I refuse help when offered because it is easier to stick to my routine.

I'm not familiar with the Apollo 16 but assume that it is a monohull.

Howard