I replaced the topping lift on my sloop rigged Bermuda 40 with a custom solid vang built by Garhauer. They will work with your measurements and send you extra springs of varying strengths so that you may obtain the lifting moment and degree of motion you desire. I can raise my boom some 10-12 feet above the cockpit (aft cockpit if you''re not familiar with the B-40) although that should never be necessary and I can retract it almost down to the helm using the springs for lift and a multi-purchase control line lead through a variable release line stopper for retracting. I have used the rig in winds of 20-25 knots w/o use of a winch although, if necessary, I can run the control line to one of the unused secondaries in the c/p. At the present I am using a 24:1 purchase but can easily double that by doubling the end of the control line if that proves to be necessary. When cruising I usually leave the boom (and flaked main) supported by the vang for ease of use. However, if I leave the boat for any extended period, say a week or two, I will generally support the boom weight with the main halyard lead to a bail for that purpose. I heartily recommend a solid vang for sail shape control...so much easier and precise than fussing with other methods.