christian a decent bodyshop will take less time fitting a roof than it will welding one woth the change of warping it thus having to do the job again

reshelling,,,,, well thats just stupid for the car it is tbh

take into account what MOST bodyshops do these days,,, they dont panel beat as much as before but cut/strip and replace panels

carbon roon is another option though,,, well not as safe as a actual roof