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It must be possible. I haven't seen anyone with the GT3 wing, but there is at least one guy on IG who put a 3RS (or similar) wing on his Carrera S. I'll try to find it.
Dundon Motorsports could be a good resource for you. They did a bunch of development on 992 aero, albeit for GT variants. They might be able to give you guidance on the GT3 wing/upright install.
Long shot, check with Tyler at APR who figured out how to put a big wing on their 991.2 Carrera T, or even @4 Point 0 who was trying to figure out how to add a wing to his track-focused 991.2 GTS. They might be able to point you in the right direction.
Not a GT3 wing but here’s a Carrera S with a big APR wing. He runs decent lap times but also modified the front aero. Even with only a GT3 wing you would probably get improved performance on track if you’re in the advanced run group.
Do whatever you want. But if you don't balance the rear downforce created by whatever wing you attach with matching front downforce, and you have kids or a spouse, add the cost of additional life insurance to your budget.