I'm adding deck lines to my Ganymede (Guillemot S&G) using tube fittings. Once the lines are secure I plan to use D-rings and pad eyes for some shock cord on the back deck. But my issue is finding a way to connect the lines to the boat. So far, I plan to use a short loop at each end to attach to the boat with a Lark's Head knot. I've tried figure eight knots (and I've read about Ashley's stopper knot) to fix the ends in the tubes near the cockpit, but they are difficult to tie with enough tension on the line. I've considered doubling the ends across the deck near the cockpit and spiral hitching them together, but I'm confident I will encounter the same low-tension issue. It seems like this would be a common problem, but I'm not seeing any posts regarding this problem. I like the idea of using toggles to add tension, but that doesn't solve my problem of tying the ends of the lines. Can you make a suggestion?