StageZilla - this is where the aw is a bit silly... as far as ive been told from a few people a the pits/police officers, you CANNOT have less than 35% grade tinton your windows, however you can have the rear passenger/rear window painted over/stickered, etc it just cant be tinted..
and from one source i heard this was only legal if you had 2 side mirrors, ie one on either side, as some cars only have a driver side mirror...
MacGuyver - the law states your rim width may be a maximum of 7" wide, unless wider was a factory option. ie..
if your car has 5" wide rims, largest option was 5", you can put 7" wide on it.
if it came with 5", largest option was 8", you can put 8" on it.
if it came with 9", largest option was 9", you can put 9" on it.
ruling over these tho, the rim/tyre must not extend past the side of the car, so if you have 5" on it, but 7" sticks out, you need to either change the rim offset, or put a smaller rim on it.
and, both rims/tyres must be the SAME SIZE, unless it came with different size/widths from factory, ie porsches with wider rears, etc.
as far as i know, all skylines had same size wheels front and back from factory BUT if you get an engineer's signoff + permit to say the rims are legal, you are fine.
also what you wrote about bov's is true, and boost controllers is true aswell, they arent *illegal* with a engineer's signoff + permit to stipulate they dont f**k up your emissions