Eventually, I'll be designing a tent to fit over the boom to cover the cockpit for short overnight trips. Since the bow always points to the wind when at anchor, I decided a little cross ventilation would be in order.
Here are a couple of pictures of portholes I figured out. The only thing not shown is the screen I want to add.. Total cost of materials was under $25.00 for two. Considering that one brass porthole costs about $90 on EBay, I'm really happy.
The wood trim (more red oak) will be on the outside. The clear plastic unscrews from the inside.