It doesn't really matter how you arrive at the correct CG location, only that you are correct. What I mean is, make sure that the 106mm is exactly what they call out, and that the location on the wing is also correct, with the plane right side up, etc. You can use a commercial CG machine, the Vanessa, or you and a buddy's finger tips, as long as it balances where it should, you are OK.

Jesse