No way a 147 GTA exhaust would fit a GT, they are loads shorter between the rear subframe and the rear bumper. Also the tailpipe position is different with respect to the location of the hangers.Even though it also took some tweaking to get it to look right the Ragazzon system by comparison in terms of how the tailpipes are in relation to the car is far more like how it should be. It does make me wonder if the Scorpion on before was maybe for a 147 GTA as the pipes really were too far inwards. Problem is I'm not fully sure, for all I know that could be how it is anyway. The Scorpion is for sale if anyone is interested, due to the uncertaintity of fitment I don't want much so could be a worthwhile buy for someone.
A 156 GTA exhaust would fit but the 156 GTA tailpipes are much closer to the passenger side of the car, not a great lot different in terms of distance from the hangers.