225 on a 20SF (too heavy?)

[uncleboo]

If I were in your situation, I would drop it in the water and use a level and tape to , at least, approximate whether it would drain properly. Rest the level on one point of the stern above the drain, hold level, then measure inside the cockpit and outside to the water. You could do this with or without people in the boat. Sounds primitive, but, most of what I do is.