Did This On 'Syzygy'
We got the spinnaker winches as a factory add-on for our H340 and we use them all the time for the jib sheets. The two standard cabin-top winches are just not enough to handle halyards, reef lines, main sheet, and jib sheets!As everyone has said, the aluminum plates are in the cockpit coaming laminate just waiting for the winches. Just make sure that you locate them properly.Our experience with using these winches for the jib sheets was good; it worked pretty well. We didn't have to add any other deck hardware; just ran the jib sheets straight back to the spinnaker winches right from the cabin-top jib cars. There were two issues that we ran into:-Although the run from the jib car to the starboard winch was clear, because of the way the sheets enter into the winches, the port side line did rub on the cabin top. We had to put down a bit of anti-chafe tape on one spot on the cabin top. -It is a long run from the jib car to the spinnaker winch, and we found the jib sheets to be prone to an over-ride when sheeting in quickly during a tack. It's OK once the sheet is tight and under tension, but due to the long run from the car, there is a lot of play in the line when it is at all slack, and we had a couple of over-rides when bringing the jib across in a tack. You really need a sheet "control point" near the winch. We are considering adding a turning block / fairlead of some kind near the winch.These two minor issues aside, we sailed all last season that way, and will continue doing so. These comments are specific to our H340. Before buying those winches, you may want to take a piece of line and check that YOUR boat has a clear and free line run from the cabin-top jib cars to the spinnaker winch position, or that you can create a clear path with a turning block.Good luck!Carl and JuleH340 s/v 'Syzygy'