That`s a good question Clint.
I think though, if you are skilled enough to cut the entire back section off and extend it, you can probably adjust anything that comes up when putting it back together.
Someone also mentioned on another thread, that if the cab gets out of whack and the doors don`t maintain a good reveal all the way around, that it is hard to get them to fit again but if the cab just gets twisted a bit, that should be just a matter of twisting it back to it`s original configuration unless you have cut metal out and sheet metal parts have separated, etc.
