The hole for the servo wires to go through was already there. Just be careful on the inside of the fuselage where you run the servo wires as they are very close to the tailpipe. I used heat resistant sleeving as well as a ceramic blanket. I am paranoid about servo wires melting on a hot tailpipe. Even if they dont touch, I have seen them degrade over time with the close proximity to heat.
If I was to do another one of these, I would put a thin plate of carbon or ply sheet on the inside of the fuselage where the bolts go through from the Alu 90 deg servo mounts. Currently they are honeycomb and when tightening down on them the feeling of compressing composite material was not great.