Good luck with regency, if u get the youngish dude I did and u act nice u should be fine.
Tip: you go in there with a nice attitude they will treat you better, if something is wrong with your car never and I mean NEVER argue with them at worst make a few comments claiming a mechanic etc did it and u didn't know it had a small leak etc. Arguing just makes them picky!
Wheels might be a little large, I know the rule is 2" larger in diameter but you have 9" wide rears which I believe is a lil to wide isn't it, I thought it was 8" from memory for skylines.
Make everything as stock as poss, take the strut bar off even tho allowed just to make your car look less racey etc. Remove all gauges if u can be bothered to make your car look less racey although below the dash is alright.
All boost controllers are illegal remove those I got away with pluging the vacuum hoses and just removing the bleed etc.
Borrow stock rims and legal tread tyres it makes a big difference to there impression.
Make sure your cars 360mm centre of wheel to lip there a lil picky on that one at times. Hire some shocks etc from FBI etc if you don't have the stock ones. There easy az to fit.
Make sure all seat belts retract if not get some compressed air and blow the mechanism out it works a treat.
If u have a small leak and can't fix it get under your car around the corner from regency and wipe it off of course steam clean the engine bay first if a reasonably bad leak.
Pods for R33's etc are fine as the airbox is hard to come by.
Steering wheel make sure its stock or at least as big as stock. Stocks better but mates have got through with bigger aftermarket ones.
FMIC's fine just make sure they didn't cut the body to fit it in!
Exhaust should be ok being a turbo i haven't heard of any turbo not passing that test.
The simple stuff check all lights. Make sure the hand brake is tight otherwise you might not pass the brake test.
I got through first time it happens just make the car look clean and unraced and you should be fine! Good Luck Luke!