I'm glad to have the roof sections either way! Thanks again. The door tops are going to be even more appreciated I think.
As I keep thinking about the problem, I keep thinking of reasons to cut it in different places! Last night, after posting, I was thinking about it more and realized that if I cut it forward like I was talking about, the cab tapers alot there. The problem with that taper, even though I have the sections from that area, is that I can't make ti match the line of the door frame there since it will, in effect, make a straight spot in the taper where I slide the front section away from the rear section. Does that make sense? Basically, my patches would end up parallel to each other there.
So now I'm back to thinking that a rear cut is better because there is a short area back there where the tops of the door frames are close to parallel (almost no taper). This is the spot that Old Iron was talking about. If I stretch right there, then that area where my patches are parallel won't be nearly as noticeable. I can still use the roof sections that I have as patch material, I just might have to cut them up a bit and weld multiple pieces in to make them work. They have the compound curves in them. Even if the curves a a little bit different, they will be a whole lot closer than flat sheet. Since I don't have sheet metal tools, i.e. english wheel, etc., I would only be able to use flat sheet if I didn't have the patch sections.
Sorry for the long post, I just want to get opinions on my thought process as I want to do this as "right" as I can the first time!