Takis,
Here are some links you may be interested in :
I'm thinking of doing this next year :
http://www.imagineauto.com/boxster02.htm
Also, great write up on Boxster mods :
http://mike.focke.googlepages.com/itisn%27tfastenough
( Mike, hope you don't mind me posting the link. Great website ! )
Hope this helps...
Nick