At 19 you are either very brave or do not yet quite understand what you are in for with a car like the GTO/3000GT.
Most of them out there are potential money pits - especially if you are going to modify something that the previous owner is ‘looking to get rid’.
My advice is to let go of the racing engineer mind set and stick to basics and making most of what you got. You don’t quite have the dream budget or facilities to race convert a likely shagged road car for the best part needs an oil change and new coilpack - let alone a fancy dry carbon canard predicted to give you 14 kg of negative lift.