Joe is right - measure, measure, and then check your measurements. When you're done measuring, lay the forestay out on the ground with all the fittings (drum, etc) attached, and then lay the foil alongside before, repeat before, cutting the foil to length. Be sure to cut it long enough so it bears on the upper rod, not on the wire. Also be sure there are toggles on both ends of the forestay. I had to buy a new forestay to get this feature. I fitted a CDI FF2 to my M-17 last spring, and it is straightforward if you're careful, (particularly in uncoiling the foil), and pay attention to detail. Uncoiling doesn't take three people, in fact I did it alone, but it does take some thinking and preparation. As Joe says, read and re-read the directions and you'll be fine. The only unrecoverable error you can make is to cut the foil too short, which is avoided by actually cutting "in place", next to the forestay. Don't worry too much about the actual measurements. I mounted the drum and foil on the forestay with the forestay lying on the ground, then carried the whole assemble aboard for attachment to the mast. Much easier that way. The upside is that you'll love the furler. Rick M-17 #633 Lynne L ************** Access 350+ FREE radio stations anytime from anywhere on the web. Get the Radio Toolbar! (http://toolbar.aol.com/aolradio/download.html?ncid=emlcntusdown00000003)