I would contact Kirk Evans of Amerisport. Google and you will find the contact information. He probably could help you with the GT5 wing. He imported and distributed the GT5S.
His phone number is: 419-874-0505
He has a reputation for high quality stuff that fits!!
I purchased his low wing with rear brake light - Beautiful. Light weight, well built, no warpage (Also has integral radio antenna). It is the one on this link, http://www.panteracars.com/evan620.html
HTH
BG.
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