No grave —- really like your sea chest something you made up? What are the measurements and how are you mounting it ? To the stringer -bottom support?

They are more common on the larger boats with several livewells. This, along with my bait tank, was one of my first attempts at building from a mold. The interior dimensions are roughly 12" L x 9" W x 8" H and narrowing towards the bottom to allow for easy removal from the mold. I don't have good pictures but you can kind of see it in the last one, I built a wedge from some coosa board to match the angle of the hull, glassed that to the bottom of the seachest and glued the whole thing to bilge with 5200. The fitting on top is to vent the air when I first open the seacock and to allow me to rinse the pumps when I get back home.