From what you describe, I'd also suggest you try an inexpensive hydro plate.
Bob's Machine Shop makes a $35.00 "stabilization plate" that may well stop
the problem you are having.
I have had good results in the past with hydro/doel/etc. etc. plates, but
I've somewhat switched my allegiance to "smart fins" to keep my boat on the
level, but your problem sounds different than that. RichG
-- manager, Carolina Skiff Owners Group on MSN
http://groups.msn.com/CarolinaSkiffOwners