Looking good Xantos, keep the pictures coming!
The manual says the C.G. is at the middle of the wingtube but is that not to much forward?
What C.G. are your friends Viper using?


I'm convinced the JR8311/8411 will fit in the stab.
In this picture I just drop in the JR8311 (8411 with nylon gear) in to the stab without doing anything.
Only the opening in the wooden former needs to be enlarged.
Ayway, I go for this option and replace the alumium stab tubes with carbon ones to compensate the servo weight difference.