Perhaps it's just me...but... I often dream to going back in a time machine, and strolling around the GM factory hand picking parts.. I really do!

I've not seen any significant exclusivity with one vendor selling "better parts" than any other. So, it boils down to buying from a vendor who knows our cars, understands the challenges, and will work with you on returns as needed. I've had good luck with Cliffs Classic Chevrolet (Portland OR) since.. well.. Cliff KNOWS these cars. I also had a good experience with H&H Chevy parts with a defective turn signal switch. They send me a new one, no questions asked, and didn't even want the old one returned.