It all depends where you take it... If you have to take it to the pits they might be a pain they might not. If you only have to take it to an ACT approved inspector i highly doubt you will fail. I had my GTR pass easy. If you can take it to an ACT approved place try to find somewhere that doesn't deal with modified cars much. I have found that they just make sure its high enough, check the lights and make sure no leaks. Then you are good to go.
But like i said i can't remember if you will have to take it over the pits... ask verms he did just move is Autech stagea across. I know he gets his done at Ultimate tunes and they where pretty good. I used to take the GTR to capital automotive in fyshwick as the guy that runs the place is pretty good.
p.s that does sound like a nice stagea.