The AC system on the GT is both very conventional and straightforward. Both the high and low side ports are under the front bonnet - underneath the removable liner. I'd recommend that you remove the liner to make it easier on the tech and then just make sure they don't lean in on the fender.
Also, if you are game, the AC system is pretty easy to top off yourself. Just buy one of those re-charging cans at Walmart or any auto parts store. Connect it to the low side aforementioned port and then start the car. Turn the AC on and fan on high and temperature on max cold. Gently shake the can and occasionally invert it for a second or two. If the can starts getting cold, it means that you are feeding refrigerant into the system. Watch the gauge on the can and get it into the right zone and don't add too much. Hope it doesn't sound hard - it's not. Perhaps a lot easier than taking you car to an AC shop.