I'm away with work so can't take any photo's but there are a few options.
I think CARF intended people to use side mount servo's which can be mounted to a wooden plate (supplied with the kit) to the composite surface over the top of the doors. I used the wooden plate and glued it to the side wall next to the door hinge and screwed the servo to that (obviously one each side). It sounds more complicated than it was - it was a pretty straight forward set up.