Thanks for your answer, ElectricBlueGT, that helps. The wheels I liked had +38 offset, so I should be Ok then. Discountedwheelwarehouse.com (I'm not sure if that's the same as Discount Tire mentioned in your post) doesn't make a disctinction between GT and non-GT in their search engine though.
Also, my 2004 PT came with non-chrome wheels. You can see the pic of my GT here:
http://www.ptcruiserclub.ru/Graphics/Front-Close.jpg
I know that that's how they come in Europe. Does anybody know if there is a size/weight/etc. difference for wheels on European GT's? I realy like how the chrome wheels look on Electric Blue, so I want to get them for summer time and save the stock ones for winter.