Really embarassing question....

[topcat0399]

1/8" hole. I'd probably throw in a ss bolt washers bevel a little 4200 and fugetaboutit...

 

[wing15601]

If the hole is well below the water line I would drill it larger, install a proper throughbolted seacock and install a wash down pump. You’re probably going to get some bird poop and bluefish blood on your boat being located in Maryland. A wash down pump is nice to have.