Okay this Sept I am hauling out and repowering and refitting TAPPAN ZEE in Port Townsend for our Pacific cruise. I do not have "proper seacocks" and plan on upgrading. I like Brian's view about Marelon because it is immune from electroisis. I have had several conversations with ART at Forespar about the NPT designation on their website and he assured me that it is a typo and their products are 99% NPS threads. I want to move the engine exhaust farther aft so it will be less likely to be submerged when heeling. TAPPAN ZEE is a canoe stern Coast 34. My concern is following seas and hydro locking the engine, while I can close the seacock for passages how much more likely am I to take in water while running in a following sea with the opening aft?