Ok, got it, your halyard doesn't go thru a turning block on deck, it stays on the mast and is cleated on the mast. So bowstring ain't gonna work. Going back to my Hobie Cat days, how about this? :
https://www.murrays.com/wp-content/uplo ... ng-kit.jpgSo, run your halyard thru a zig zag of blocks on the mast, thru a cam cleat and tie off on your slippery horn cleat. No need for a helper rope, but you may want to use a "tapered rope," strip the cover off the line for the last 22 feet or so - the length of line left when the jib is fully up. For the two blocks in the "zig-zag," one is fixed (cheek block, screwed to mast), the other moves. To tension the jib halyard, pull on the moveable block, either up or down the mast, with as much purchase as you need. Use Racelite blocks to keep the prices reasonable.
So, if you want to stay on the mast, you'd lead the halyard down to a cheek block, turn back up to a single block, down to a cam cleat then your horn cleat, all on the mast. Then you'd have a 2-1 pulley leading back up the mast, attached to the single block. Set it up so the tail comes back down to another cleat on mast. Done!
You'd need a cheek block, three single blocks (or two and a becket block), an eyestrap, a camcleat, another horn cleat. $60ish, not bad. Speak to the owners at racelite, they'll address any questions on load.
What do you think?
Tom