A fellow worker bought a '99 Gen 10 F250 5.4L that has a leaking exhaust manifold. On closer inspection, it appears that the back two bolts or studs are broken and the others are very badly rusted. (I'm afraid to ask this part) How bad of a job is that to remove what's left of the stud or bolt? Is this something for the faint of heart, or is it best left to professionals? If you guys were doing it, would the cab come off?