The elevator servo is mounted on cross blocks which are
attached to lite ply that was added to that area inside the
fuselage.. The servo was installed into the rear of the
fuselage to help shift some weight towards the rear of the
plane.. An additional benefit of doing this is having shorter
linkage so less likely for linkage to flex under load.. It also
allows the linkage to be totally inside the fuselage so it can
not be seen..
In order to access it for adjustments, to get to servo arm,
attach linkage, or to even replace if ever needed the servo
there is a hatch on bottom of fuselage as shown.. This is
mounted with two light wood dowel pins and has a single
buttonhead screw attaching it to fuselage..