It's my understanding (though I may be wrong) that all the sheet metal is made by the same company. (fenders, hood, etc) Furthermore it's also my understanding that they all really stink - the fenders I mean. There are still parts cars out there (though I hate to volunteer that because there are less and less good LeMans and Tempests because they have all given their lives to keeping GTO's on the road.) The good news is that there are thousands of 1968 Pontiac a-bodies out there (the largest production year).
2005 GTO Daily Driver
1969 Custom-S Project car
1971 GTO 455 in process of rebuild TH400 NEED A NEW REAREND!!!