I'm having a busy Boxster weekend and took care of a few items on my old-neglected Black '99 (AKA "Dirty").
Here are some pictures to help illustrate the procedure that
particlewave mentioned.
Between these pics and the Pelican Parts Tech Articles, it should be
almost easy.
Porsche Boxster Door Panel Removal / Mirror Switch Replacement - 986 / 987 (1997-08) - Pelican Parts Technical Article
Porsche Boxster Door Lock Mechanism / Door Handle - 986 / 987 (1997-08) - Pelican Parts Technical Article
Putting it back together: I recommend latch first, then lock lever, then handle.
Good luck :dance: