It seems like the anecdotal "My mate did it and got away with it" and the age old "Cops don't know anything"about imports" is the thrust of your argument; EVERYBODY has a mate that got away with everything. I was the guy that got away with nothing; EVERY TIME I did something, I got nailed, so I just had to stop doing stupid shit, otherwise I'd have lost my license.
Trust me when I tell you, more than you think know what imports are, the Green Valley HWP centre has walls LITERALLY covered with pictures of P plater illegal vehicles and illegal mods; just so police can familiarise themselves with them. You're having yourself on if you think they don't know.
You're telling this guy to disregard GOOD advice (not always the most "fun" I realise), follow the rules then do it when you're allowed to; and do something bloody stupid. As if having P's on your car doesn't make you enough of a target; lets add an illegal vehicle...
Rant over.
Back on topic; Slip on a pod, remove the cats, get a shitarse loud exhaust and some ugly arse chrome wheels. Then you'll be fined and defected off the road for driving an illegal vehicle on your P's and I won't have to worry about an uninsured pinhead running into me in a car he cant handle.
REAL ADVICE; Put the 350GT in the shed, go buy a cheaper P plate legal car, learn to drive, then go for your life once you have a full license. If you need advice on mods for your V, check out the "V Series Skyline" section of the forum.