Yep that is exactly right. This is the one thing most of these young guys don't understand when talking about "taking a turbo off". This does not make the car legal. The car is complianced and registered as a turbo car therefore it is irrelevant if you take the turbo off, still illegal to drive. (might sound a bit stupid but thats the case).
The only way i can think of making it legal (at least in QLD) is going to an engineer, getting it mod plated for not having a turbo, then re registering it as a non turbo. This still might not be legal i dunno. But if it was it would be the only way to do it and really if your going to all that effort, for f**ks sake just buy a non turbo GTS.