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Or the owners mods for the 27'. There's information on replacing the front trapezoidal hatch, they are not made anymore but there is one size that is pretty close. If I recall there is some modifications needed to the cabin top.
I decided to build new hatches for mine and I just installed them this weekend. I still have some cleanup work to do but they are in. Hopefully this cured the leak I have that runs down the liner onto the v-berth shelf and in the head behind the sink. When I removed the front hatch I found a few voids between the cabin top and the inside liner.
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