Well I really wasn't talking about trying to use the hobie piece directly but more like just trying to find out the dimensions of a hobie tramp. The idea was to buy a cheap hobie tramp on ebay for like $50 and have it cut and sewn to fit on the 474. How much does tramp fabric cost new? I would go with the ones linked, but I've been told that having only lacing on one side that it will stretch and sag. Appparently the 474 originally had a tramp with bolt rope on two sides adjacent to each other and lacing on the other two sides....so it could be kept tight in both directions.