My catalina 30 has the original Lewmar rope clutches for the halyards and mainsheet. I'm thinking of replacing the rope clutch for the mainsheet to a cam cleat to make it easier to trim the main while single-handing. Because the clutch fitting is also shared with the main halyard, I'd end up having to change that, too.Has anyone done this, and if so, are they happy with the results? Any general advice? I'm considering using Harken model 150 or 280. They have a maximum load of 500 ld. Does that should sufficient?