My center cockpit ketch had the aft sink plumbed 10 feet to a tee in
the cockpit drain. The head (MSD, blah, blah, blah) was plumbed to
the through hull directly under the aft sink.

Now, I'm trying to connect these back up...

I've a bit of a problem running the sink drain to the cockpit drain
through hull.

I think I should have a problem teeing the sink into the head through
hull....

I'd rather not put another hole in the hull. But I figured somebody
here would have an opinion....