Ok I've fixed it now, I shaved some off the bulkhead and probably too much off the ballcup (watch it break as soon as I drive it) oh well - it was pretty smooth until that
Servo is flat to the bottom and I've got the manual suggested shims - but the link is too high anyway, wouldn't matter how far forward/back the servo was, it will always hit the bulkhead. (well, until I've shaved lots off)