I have a 14″ Grumman flat bottom , I measured and sawed ( and resawed to fit ) a hole, in the middle seat that a 32 quart coleman cooler fits perfectly , and rests on the floor. I lost all the foam in that seat ( hardly anything at all anyway, two small waterlogged blocks)- so I added a bunch more in the rear , and in the front, (“GREAT STUFF”- get it at any hardware store). Use that area on the sides of the cooler (inside the seat) for storage. Put some rubber seal on the edge of the hole as it is rough from the saw. I didnt aerate mine but I’m sure you could do that, as I might also – looks good too.