Zeke, You have the same problem I have, only mine is worse. I drilled out the spot welds along the front of the roof and was going to section in a piece from a used roof. My inner header was rusted too so I cut it out and found a big mess. I am going to end up replacing the entire inner & outer roof. I am going to keep update pictures in my Photobucket so if you want to, check it out. My Truck Thankfully I got a complete outer & inner roof from JIMBO59 in the parts for sale forum. It was about 1/4 of what new parts cost.

1957 Chevrolet 1/2-ton Stepside LB in the Gallery
My Photobucket shots

The person who has nothing for which he is willing to fight, nothing which is more important than his own personal safety, is a miserable creature and has no chance of being free unless made and kept so by the exertions of better men than himself." - John Stuart Mill (1806 - 1873)