Hi,
the filter should be replaced. Don't forget to clean the magnets in the sump, that's even more important than the filter. Replace the sump gasket as well.
Everything else should be straight forward - oil away, new filter, cleaning, assembly, CORRECT refilll. Do you know how to refill properly? It's a tricky. You'll need an ATF dipstick as well (is missing, I guess).
Bastian
