There are people that claim you can do it without pulling the cab and even a few vids on youtube showing it, but I can't see it happening on anything that has the slightest bit of age/rust on the bolts. Supposedly you can also get away with just pulling the front body bolts and hinging it on the back two bolts to get just a little more room and it lets you get the downpipe out of the way. That probably would have worked and I kind of wish I would have tried, but working on this thing was killing my back and I ran out of patience with it. From what I understand, people that regularly work on these things can have the body off faster than I could probably get a few of the body bolts loose!
This guy has a good video on just tilting the cab the get to the back bolts.
