Yep.. you don't want it to tight, I'm no glass expert....I'm guessing 1/4" or so.. this post should probably be in the glass and paint section.I’m replacing my floor and front of engine bulkhead. Both rotted out. How tight to the hull do I cut the wood. Do I need to leave a gap and tab it with fiberglass to prevent it from putting stress cracks in the hull. Boat is a centurion tunnel. Thanks guys.