I, like many others, found the jib clam cleats on my 240 to be fairly useless for singlehanding. Pictured is the modification to a cam cleat on a teak riser block. The metal plate is a piece of stainless sized to fit the pad beside the rope clutch.

See Starboard overhead view

I was able to use the existing clam cleat hole for the forward end of the plate. Two holes were through-drilled to secure the clam cleat/teak riser. All screws are backed with a large washer and bolted below. Access is afforded by the inspection cover inside the cabin.

See Port view

The port side is slightly different due to the single clutch. The teak risers are necessary in order to allow the proper angle to lock the jib sheet into the cam jaws while seated well aft.

See Port overhead view

The rear hole for the original clam cleat is hidden by the plate. The hole was filled with 3M 5200 before fastening the plate.