While changing out the control line (the loop line that forms part of the topping lift and connects to the vertical nylon lines on a Dutchman system) we lost the critical dimension between the two clamping blocks. I used proprotionate triangles to compute what I thought the distance between the clamping blocks should be, but we are still off by 1-2 feet. I know the distance between the blocks is critical for the system to function properly. We have thought about removing the sail from the boom, lay it out on the ground and measure the distance along a chord between the clew and the head of the main. It is alot of work to remove the sail. We are leaning toward a trial and error approach, which may also be alot of work. Does anyone know the dimension between the dutchman clamping blocks on the stock sail for a 1991 37.5 legend?