We use the original cleat, cleat location, and single sheaves in each of the gooseneck
and boom end castings. We substitute ball bearing Harken blocks and create a simple cascade purchase inside the boom in place of the two original single blocks to create more purchase.
The photo above shows the layout of the blocks to illustrate how the system works, but all of these components are installed inside the boom. The forward block is shackled into the original hole already located in the gooseneck
(top right corner of the photo). One additional hole must be drilled in the flange of the gooseneck
on the opposite side from the original.
The block in the bottom left hand corner of the photo is swaged to the actual outhaul
wire. That wire continues aft then exits the boom as usual through your existing sheave in the boom end casting.