My understanding is that your porsche dealership needs to turn it on with a PST2. Some say that it'll cost you some, some say that their dealer turns it on for free. Either way, unless you get the stalk installed, you can't cycle through the displays.
Thats what I'm trying to do. It looks like the parts will be under $100, but the actual removal of the airbag, steering wheel, and instrument cluster (to get to the connector) is quite a job.
I know tool pants sells 3 DVDs that show you how to do that hack plus a bunch of other hacks, but it sells for like $100. I'm sure it is a good instructional video though.
Check out
http://www.whiteson.org/boxster/mods/obc/
Check the bottom for magic mtn dan's pics. That shows some pics of the install.
JBG