I am building a Boxster for ITR in SCCA. I decided to design and build my own strut housings and use Koni 8611 1257 double adjustable strut inserts. First it helps to have a friend that has a CNC lathe in his garage. We made the prototype housing yesterday. I need to make a few adjustments in the height of the strut in the knuckle. But over all I am very happy with the way it turned out. I am also going to use a 6" spring instead of an 8" one and also change the upper spring perch.
Blake