Dear Alfonso,

You have to cerfuly check your H.Stab incidence angle. There is no need for the ailerons to be 1 mm down for
a straight and level flight. Good adjustment of the incidence angle and CG will make your plan go down straight and ailerons at 0.
you can adjust the angle on the H.Stab and put both in -1 angle to start with. You can start from there and fine tune as needed.

Very best regards

Amram Leshed
F3A Israel