The first clutch I ever did was on a DR350- I procrastinated for 3-4 months until I finally did it, anit was pretty easy. Once you get the case cover off, you'll see the basket, there's usually 6 bolts(nuts? ) holding the cover on. Use a penny to lock the gears from moving if the bolts are reallly tight, you wedge it between the back gear on the basket and it's drive gear.
Once you get the cover off, you'll see the plates & steels. Slide them all out & replace with the new units, in the same sequence, plate, steel, plate, steel. Oh, also
It's a good idea to soak the plates in some oil before you put them in.
A case cover gasket's good to have too, in case the old one tears or breaks.
Good luck, Lefty.