I put the horns into the ply no matter what it did to the line up. Mine were only offset a little. The Chip-ball-bearing horn foot-print is a triangle and causes this miss. It does not seem to hurt the actual throws when you hook it all up.

You could lay in some new ply if you can't live with it. Also you dont need a big arm on the servo. Four ailerons will give you a heck of a roll rate if you want it.

Attached is a construction photo showing servo wheel. The horn was moved forward for actual screwing into place. Make sure you remove the covering under the triangle and put some CA there as you screw it in place.