There were a few (Gen5) at the last Dream Cruise. I was there for part of it. Mostly it seems everyone has a meeting place to hang out, because there are a TON of spectators. Then they will cruise out from there. If you look in the Great Lakes section of the forum there are a few different threads about it...
http://www.camaro5.com/forums/showthread.php?t=34402
http://www.camaro5.com/forums/showthread.php?t=35206
http://www.camaro5.com/forums/showthread.php?t=37633
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