Hey guys, I work with conversions like this-among many other things. I can not stress the following enough:
If you do have someone do the conversion, CHECK THEM OUT THOROUGHLY!!! Your life will depend on it!
This will be a major project-and will always be followed by problems. No mater how good the conversion is done, it will never be like a factory roof. Our cars produce so much HP and tourqe that the frames flex and cause stress to the body, ecspecially the roof area. Even with proper bracing, good welding, and planing you still have to transfer to the stock body somewhere-and that will be a weak point under stress.
Personally, I would not recommend the conversion.