The cockpit rim gives you something to snap on a skirt (C1) or just leave it off and paddle it as an OC1. The cockpit rim also gives you one more added defense against water coming over the top of the boat and splashing inside. It also gives you something to grab on to dump water out of the boat if you are paddling it ala-OC1. The rim does add 1-1/4" of height but it doesn't interfere much at all.
The cockpit rim itself took me countless hours of thought, a recycling bin full of beer and made enough fake polyethelene snow to cover a Christmas tree by the time I was done. Like most things in life if I did it over again I would change a couple things... (keep in mind I was working with a hole in the top of a boat that had already been cut open)... the cockpit rim is made out of two pieces of polyethelene. ( http://www.usplastic.com/catalog/produc ... 5Fid=10369 ) The bottom half is 1" thick and the top plate is 1/4"... if I did it over I would use 3/4" for the lower half and 3/8" for the top plate... although I do have plenty of surface area for the sprayskirt to seal. The rim is 28-3/4" in length and 20-3/8" at the widest point. These dimensions could be smaller on the production boats Jacques will be making but like I said... I was working on the existing hole already cut from the factory. It could easily be 6" shorter in total length by the time things are said and done. All the cutting was done with a router and patterns I made based off the factory cutout... and two more cases of beer. The hardware is all stainless (thankfully I have a buddy who works for Fastenal...another case of beer) and seats totally smooth on the top plate. There are 52... count 'em 52 screws, washers and bolts holding this sucker down... overkill probably but when I seal it to the hull I don't want a drop of water coming in through under the rim.
The hatches.... ah yes. I looked high and low for 6" opening, o-ring sealed hatches and found ones anywhere from $8 all the way up to $40 a piece... I opted for the top-of-the-line from Hobie because they are hinged (can't lose the lid), had the ideal fit for the deck (nice-n-flat and the deck wasn't designed for a hatch), and have this bitchin one twist concealed knob to close them... they are slick... a little pricey (like 12 good six-packs of beer for the pair pricey) but worth the money in my opinion. The Hobie part# is 71701001 which comes with a ring to attach on the underside of the deck. (Do NOT order part# 71701 as this is a top piece only replacement item!) I ordered it from a local sporting goods store ( http://www.coontailsports.com/cgi-bin/cshop/shop.cgi ask for Lisa) that carries Hobie kayaks... you can also find them online but watch out to make sure you get the right part#. One of the HUGE bonuses of adding the hatches is the simple fact that you now have access to your airbags and/or any gear you want to take along on the river. The grabloops are made from 1" tubular webbing with 5/8" push-lock transmission hose inserted into them. The hardware I used to bolt them down was overkill but I had to seal the holes where the grab-rope went through previously.... like I said before... if I need to paddle the boat bone dry... it's going to be bone dry.
Jacques (ESQUIF) is working on making these changes for the 2007 models... no word yet on a release date so stay tuned.
!
! The boat just begs for a C1 version.
rodeo-clown 
... the big problem is you'd need a 7" waist to fit in the darned thing!