Normally, of course, I wouldn't remove the entire engine from a truck just to replace the exhaust manifolds. But a combination of multiple broken studs, extremely tight access to their location, and severely corroded fasteners forced me to go with a much bigger job than it normally is. Considering how much welding and open flame heating I had to go with it was definitely the right decision. Trying to do all this in place would very likely result in trouble or a poor quality job outcome
The job is not as complex as it might look. It is time-consuming and had a couple of difficult points (notably, starter motor removal and installation and one of the cabin mounts that got stuck in the frame) but generally, it is something like a big 3D puzzle.