dodge dart rust free roof skin

I'm really looking in tennessee. The last roof I bought for it was in atlanta but it has rust in the roof rails. The roof had rust holes in the rails. I got all the rust out and welded up all of the pin holes. Where I drilled the spot welds with the standard 5/16 drill bit....some of them were really close to the roof rail leaving not flat surface to reweld. The next time I take a roof off of a structure I will use a 1/8 dril bit and a seam buster. I built the flat part up with the mig gun but its kind of brittle. And when I ground it to shape I ground it too thin. I could really just use some roof rails for this. My donor roof will work but it isn't. As perfect as I would like