Here's how I dealt with the back cap latch/security and leaking lid issues.
Removed and junked the original cap latches as they were worthless. Replaced them with hardware store hasps.
https://drive.google.com/file/d/0B6l8KN ... sp=sharinghttps://drive.google.com/file/d/0B6l8KN ... sp=sharingTo keep the cap from rattling around I installed kayak hooks and bungees similar to the current Hobie design.
https://drive.google.com/file/d/0B6l8KN ... sp=sharingTo eliminate leaks at the front lid I got a 55 gallon plastic drum and made a MAGNUM lid, then secured it with bungees.
https://drive.google.com/file/d/0B6l8KN ... sp=sharingI used this product (Home Depot or Lowes) to make a gasket/seal at the back end, inside, about an inch in from the edge (not visible in the photo)
https://drive.google.com/file/d/0B6l8KN ... sp=sharingI've been using the toybox in this configuration now for more than a year with zero leaks or security issues.
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Hobie 16 (3 formerly)
MacGregor 25 (formerly)
Chrysler Dagger 14 (formerly)
NACRA 5.0 (currently)
High Point, NC