Thanks guys, both the current main, and the A main I'm contemplating using, have the hard plastic tubing for a bolt rope. Does this affect anything? If the luff were to pull out of the track, is there any chance of damaging the mast/ luff groove?
Lee, I can envision the head wanting to pull out if it has descended much into the mast curve. The A sail is 2' shorter in the luff, do I expect to use a 2' tether to the masthead, so I don't think it'll be very far into the curve. I was sort of expecting to just tip the boat over to rig this set up. So connecting the tether, and releasing it would be no problem. And it would then be easy to secure the headboard to the mast with a short piece of vectran.
And the foot of the A main is close to a foot shorter thna the Bim main. Either I continue to sheet from the now substanially forward clew loop, or secure the clew to the boom with an outhaul, and sheet from the aft end of the boom, for a more vertical mainsheet pull. The lightweight aluminum tube(boom) likely wouldn't handle that load. I'm probably in need of a stouter boom for this high wind rig. Or maybe the aftward pull of the mainsheet attached to the clew isn't such a big deal, as I'll be looking for a flat sail for these conditions, and the outhaul forces and reduced mast rotation that this arrangement would produce, might be acceptable.
More opinions? Thanks!

Dave