I saw a Catalina 250 today with mainsail roller furling. It furled vertically on a line similar to a jib furler (although I can't see how that would work well, I need to go back and look at it again). The sail was tracked in the boom. Is it possible to add systems like this to a boat like a C250 without replacing the mast? How do they handle battens? Sign me, Mystified and Amazed...