Steve,

Actually the N20 cleat is on the traveler car itself - there's no mount on the rear beam. The Nacra F18 is the same way. The N6.0 has the rear casting on the rear beam where the pivoting cleat is firmly mounted (Like Wouter's pics above). I too am in the process of changing my F18 over to a center mounted traveler cleat because I just like the feel better.