Even more so: Since the thustline is so high, and the CG is WAY below that and so is all the drag, the thrust angle in a Flying boat is usually UP as much as 3 degrees. Otherwise when you punch power, inertial and drag forces want to cause it to pitch down. Also they give FBs T-Tails so that the downwash from the upthrust hits the elevator to help counteract the nose-over moment especially on sudden acceleration.

With up-thrust it is necessary to compensate for the misalignment of the airflow through the propeller disc, so right thrust is also dialed in 2-3 degrees.

I'd start with up three and right three degrees. If it's too much the plane will balloon a little. That's better than suddenly powerdiving into the dirt.
Here's full-size Lake amphibian. Even tho it's a pusher you can see that there is a lot of upthrust.