This is the best I can do. The track was originally for the jib blocks to slide on. It is about 18 inches long and just screwed onto the boom. The clew is lashed, tightly, to a slider and the outhaul tightens it up if needed. I don't actually adjust the tension all that much. In theory, if the winds are light, slacking the sail foot makes better use of the wind. In practice, if the wind is light I tend to put my feet up and have a cup of coffee.