My new ship was doing the same thing. Added a little nose weight it went away. I started making some line adjustments and the hunting started again. I got my lead-outs a tad too far forward. Got them moved back a hair and the hunting went away. Use some clay on the nose first, see if it works. As mentioned, some down elevator may help...a little "slop" also. To quote my coach. "An adjustment here effects the adjustment over there." You have got to go slow and small until you find that "happy medium."
Norm