Those aren't cams, they are just tabs. Stick with the hidden bungees - they are a lot quicker and easier to use. -Wes

You may bethinking of a "Moby Latch". In that case see http://www.byg-kajak.dk/moby.htm

I'm pretty sure that if you search the shop tips or look at the flush hatch kit description you can see how it's done.  Basically you cut out tabs of plywood, drill an approptiate size hole.  Epoxy the heck out of them to seal it.  Maybe put a layer of fiberglass on one side for added strength.  Then use stainless or brass bolts with lock washers to hold them in place.  Remember to drill fill drill.  then a bit of sealant keeps the water out of the bolt holes in the deck. Put the hatch in place. Push down, Turn the tabs and you are secure. 

I have one boat with bungees and one with tabs. Both work.  Bungies look really cool but the tabs aren't bad looking.  You can paint the contrasting colors to go with a decorative stripe on the sheer and coaming.  Maybe make some of mother of pearl?

Ebony?  Be creative.

Have fun.

Ed

I ended up going with hidden bungees on this one just because I am in a hurry to get the thing in the water.

 Definitely going with mother of pearl cams for my next build!

I would suggest something other than mother of pearl unless it's very very thick.  That stuff is very brittle and, when it breaks (not if), it is very sharp.  It will cut the hell out of your deck and anything near it...

It would look very nice inlaid in some nice hardwood though.  Again, though, it would be likely need to be very thick and not as practical.

FrankP