I have come up with the only feasible solution I can think of and might be willing to do:
Replace the Saito .62 with a Saito .40. The .40 would fly it ok off of land, but would have no vertical performance. It might not even be enough power to get it off of the water with an additional pound of very draggy floats hanging below. I dislike "angry bees", so I am not putting a tiny, screaming 2-stroke on this thing.
I just weighed it, and it is 5 lb, 0 oz with the .62. I also just measured the nose and tail moments, and they are about 1:2. The .40 saves me about 7 oz, and that reduces the needed weight in the tail by about 3.5 oz. If I move the servos to the tail, that knocks off another couple of ounces needed back there, which gets me pretty close. I undecided on whether or not I am willing to spend about $250 and do serious hatchet job on my beautiful plane to solve this nightmare problem. I may just light the stupid thing on fire.