Mike, my friend Kirt Metts has a roller furler jib on his 5.7, not a self-tacker, but he made a smaller(lowered) bridle that allowed him to pin his jib within 2 inches of the front beam. This worked so well I did the same on my 5.0 but I always wanted to go self-tacker. I felt the jib was a little oversized for the 5.0 and way oversized for the 6.0, not sure about the 5.7, never owned one.
So you could probably lose a little and still be quite powered up, and with a spin or a reacher it wouldn't matter anyway.
keep the pics coming!