One change I made during the building process that turned out well was to cut out the hatches but leave 4 sections 1/2" long uncut until AFTER the hatch rim and hatch stiffeners were installed.

This makes a lot more sense to me than cutting it out completely and then trying to realign it to make the hatch rim. One must only be very careful to cut on the line so the four sections form a fair curve when they are connected.

My friend Kurt Maurer tells me this is called 'tabbing' which sounds appropriate.

John
PS: I didn't have any carbon to make the hatch rim black, so I used sanding dust and really like the brown look.