Moving the CG back is the right way to go. BUT it's not a great idea do jump all the way back in one move. I would go back perhaps 1/2 or 3/4 the distance. Test fly it and then go back more if needed. If you know it takes 3+oz to get the CG to where you are now you could test fly by adding only 2oz at first and then if needed tape another oz at the air field and fly again. See if that is the right place.

The Ultimate is such a short fuse that once you go back too far by just a little, its too late.

If its nose heavy it will land hot, if its tail heavy you don't need to worry at all about landing, quick thumbs may save it, but not worth the risk.

tonyc