Hi All, I did something very similar. I cut some half circles of wood (scrap maple) and then cut them in half, routed a U shaped groove (mounted a straight fence on a router table and follow the outside contour) in each half to form a channel for the bungie and then glued them back together. Then drill two holes in the deck and epoxy the blocks underneath. After making the blocks and thinking about the installation it occured to me that it might be hard to open the hatch without untieing the bungie or having one raised fitting. After some pondering and wandering about in hardware stores I found that west marine sells something called a "shock cord to webbing connector". The end of the shock cord is inserted in the end and clamps down on the cord. The other end has a webbing loop. I sewed one end of a 1" slide release buckle to one connector (using about 2" of webbing) and the other side of the buckle to the other connector. After the bungie is treaded thru the deck holes the two connectors are put on the free ends and the hatch can be closed or opened by the buckle. So far it worked just dandy, but I do carry an extra premade set just in case.

Bob