gday mate, i got my 33 from ACT and had the car blue sliped with 17x9's on it and a 3" turbo back zorst (with a 3 chamber muffler in place of the 5" cannon of course)and it was fine, the only thing to guy said was "you might wanna get your rear tires replaced soon",
i agree with the above find a new mechanic.
also with the 10 year old thingy, the RTA told me its 8 years and its random, when you register the car, the computer will randomly select you or not (i was told this because the Rtard who complide my line did it in 2002 so acording to the RTA i have a 2002 R33)