HS-81s might be a tad on the fragile side for a .40 sized fast aileron. The standard servos will probably stand up to the beating better.
For routing the wires from the servos, I roll up paper into tubes a bit wider in diameter than the servo plug, and pull the wire thru with the string.
Mount the servos about 2 bays out each side for best resistance to any flutter.
Other than that, plain common sense works well in mounting the things. No binding etc.