Twisted Hobbys CRACK PITTS Assembly Manual page 17

If using the power combo servos you
should have stock horns like pictured
above, if using other servos, nd the
horns that came with them that are
similar.
Same basic process for the tail servo
horns... apply some Welders to the
under side of the stock horn and attach
the extension.
Rev: 2015.09.18.v01a
From the under side of the stock horn,
apply some Welders to each of the
arms.
Above picture shows the extension
attached to the horn from the under
side and butted all the way up against
the center part of the stock horn.
Install the differential horn as shown, if
the center hole is a little big, just center
it in the opening, if is not super critical,
just get it as close as you can.
Repeat the previous two steps with the
other tail servo horn and set all the
items aside to dry.
page 17