I don't think it's that simple...
I'm 6'9", and I'm super comfortable in the sunroof-less, but the sunroof one doesn't cut it for me.
My dad however is 6'6" and said he can't comfortable fit in my sunroofless camaro.
I like to lay back so my arm is straight when I drive. I fit comfortably on other cars from acura integras to a smart car. My pant size length is only 32 though, so I have a tall torso.
My dad can't fit in ANY cars, and he's only 6'6". He now drives a Caddy DTS, but can't fit in the DTS with a sunroof. Since the new DTS only comes with sunroofs, he's actually switching to the Mercedes E550, since he doesnt fit in ANY of the caddy's except the trucks.
I however, at 3" taller, can fit fine in all of them.
Ultimately I don't think you can simply say whether or not certain heights can fit with enough headroom. Everyone sits in different ways, and have different proportions (Arm length for example matters too!)
At my height however I kind of just go with the "Maximize interior dimensions" mentality Whether I could fit with the roof or not, I prefer to maximize the interior, so I don't have to worry as much, can wear a hat, etc. I did that with my Truck (Used to have a '05 F150), even though I fit with the sunroof.
The other problem with having a sunroof with the Camaro, is if you ahve any plans to keep it long term, every sunroof leaks. 10, 20 years from now I think a sunroof will just be a PITA.
2010 Camaro SS modified extensively. Swapped out the chassis for a full 2011 Ram 1500 Big Horn 4x4, the drivetrain for a Corvette Z06r, the Body for a C2 Camaro Z28, and the interior for a BMW e90 330i.