Hi leftrack
I have not looked at the 60 size bird but if you are in a club you may find one of the guys that has the manual for the G/S bird, and if the wing construction is similar you could add mounting rails between rib's t-4 and 5 lay the servo on it's side and use an exposed arm.
Hope this helps
Cheers Bob T
AMA13377 Corsair Brotherhood # 6