The pipe is twin walled, so the air being draw down the gap keeps the outer wall relatively cool. The thread starter Hawk is still flying 15 years later, same servos as built with and I’ve never had the pipe out. My pipe is hard against the elevator servo plate because I raised the plate on production kits after finding a thrust line change necessary. You could either paint the bottom of the plate with BVM heat shield, or use some Alloy tape as a reflector shield, but it is not critical.

Thrust pipe cone position at the front could do with being centred on the top (sitting on wheels) of the turbine rails as it’s always needed a little down thrust for perfect trim. Then depending on your turbine mounting strap, mount the turbine central on the cone.

Again because the outer wall is cool it just slides into the rear hole.

Dave