Not to discourage you...but by cutting the roof for t-tops you will severly weaken the structure of the car. You'll have to fab a framework to keep the car structurally sound. I would look into swapping over the convertible brace, as well as any other frame bits.

If you try this...make sure to post pics...I'd love to see it done.

I had a '79 Trans-Am 6.6 with t-tops...I loved that car!