I first took one apart around 1959 as a kid. They haven't changed much. Still do it occasionally to refurbish used ones I find, but I would be inclined to field strip it, and just give it a blast with some solvent or other (disc brake cleaner) and a shot with an air hose. I have done trigger jobs on a couple of them, and even when proficient it's a bit of a chore.
The average person can do it with a good set of instructions, but thought I should point out that there is an alternative.
BTW I recall one of those sets of instructions that was drawn incorrectly...