Put the focus back on the bench and set up the wings 0/0 degrees. Set elevator at neutral.
Test fly and shift CG backwards to compensate for up elevator trim.... keep doing this until the aeroplane flys without any trim or any need to change incidence. Roll test inverted hands off(ish) and knife edge hands of/ horizontal fall attitude.
Do this until things get pretty damed good and then and only then start playing with the wing incidence in very small ammounts (to eliminate any building cock-ups) taking a written note of changes so you can go bacwards.

You'll be getting very close but you'll never find the absolute perfect set up...even between 2 Focus's. I'm getting happy when I take a simple 45 degree upline, roll invered and the aeroplane follows exactly the same track.
Yep it's difficult when thing get neutral...
try flying straight and level, then reduce te engine to idle... the aeroplane just keeps flying straight and slowing down!!!! untill it just drops, falls out of the sky... very strange.