If they remove and install the pans to be cleaned then that makes life easier but I would not do it for many reasons besides the liability and insurance issues.
I don't work on heavy equipment, not certified or have years experience doing so, so I don't do that kind of thing, I just wash them and if they need certain parts washed, they remove them so they can be cleaned and then they install them later.
I am sure that there are some guys that will remove the pans and other parts to be helpful but that is personal preference, my preference is to leave that to the guys that do that for a living and I do my job, just personal preference.