If you go on YouTube and search "Camaro T-Top Conversion", you'll find plenty of videos on the subject.

 

i dont even think you have to cut the roof. i havent looked into it yet, but you should be able to remove the hole top and swap it for the t-top roof piece. like others have said all fourth gen coupes start life as a t-top car. if you take out the head liner you will see what i mean. ive been putting though into go from t-top to fixed roof.

 

you do have to cut it because youll have to take the skin off the roof then you have to cut the supports on the out side of the roof like where the top of your door window meets the roof but its looking pretty simple on the 4th gens just wanna find out about the 3rd gens on doing it

 

I know someone has done Bike Trials the "cut the roof skin and Bike Trial Seller put in the parts" T-Top thing before. Whoever did it (not on this sight) did a pretty good writeup with good pictures of Bike Store the whole process. Unfortunately I can't remember where I found it. I would love to see a step by step process. If you Bike Shop do a nice write up it could be a sticky or atleast a link in a sticky. Its a pretty common question.