back in the day a bunch of us built one, by using 2x2 stainles square tubing about 8 inches wider than the cockpit floor width, so no quite as wide as the cockpit between the seat back, positioned about 8 inches back from the picture above, used 2 more pieces of square tubing mounted to the virticle sides of the cockpit just below seat level, This way it is removable... I used a harken car that allowed adjustments from either end of the traveler... worked pretty well. for just cruising we added a simple eyeloop in the center of the step to attach the mainsheet to, so as to make room when not racing.