On a 6 Speed… Instructions say to drill a hole and insert a drywall-type screw and then, using prybar/pliers you can extract. I found that part to be true.
The tricky part was putting the transmission seal back in! Make sure you get it in FAR ENOUGH! If you are replacing the Throwout Bearing guide Sleeve, as you should, take the old one, invert it, and insert it FORCEFULLY (up to and including banging it with a mallet HARD). It MUST SEAT very well up against the lip of the transmission housing to seal.
My PO did not seal it well and ruined the clutch/flywheel/Throwout Bearing. There was also a couple pounds of grease mixed with dirt INSIDE the tranny housing…it was a mess!
TEST IT BEFORE YOU INSTALL:
CAREFULLY tip the transmission housing forward so you can test the seal for runs, drips or errors. Also, IF you notice ANY transmission fluid leaking out at time of re-assembly… the seal is NOT SEATED ENOUGH.
Here is a pic of the seal in question.
Again, this is a Boxster S model, with a 6 speed. The 5 speed has a larger flange and is a larger diameter.
Hope that helps you get it together!