1. Turbo is simply not capable of airflow @ that pressure and won't MAKE 30-35psi.
2. ECU's do not compensate
3. You should never go over what the car is tuned for, simple.
A T04Z is a 400rwkw+ turbo. You have a stock motor... Do the smart thing and leave the GT35 on there before things get out of control and cost you 10k in rebuilding.
The ECU has little to no relevance to the power. So if you are buying a link thinking you'll make more, you couldn't be more wrong.
The T04Z is a larger turbo, so it will make more power on 98 as it doesn't need to run more than 20-22psi to make 400rwkw on 98... Where a GT35 would need 25psi or more to get to 300rwkw and that is basically the limit of the GT35 anyway on 98
GTR stock AFMs run out around 300rwkw. You can "tune past", even to 350rwkw isn't a major problem - but it's not recommended overall as best practice.
And again, it's not a question of BOOST through the AFM - It's about the measuring of the airflow - which is related to boost, but it's simpler to not think of it that way
I'm interested to see how a GT35 is still running stock piping... Can you show a pic of the engine bay?