Yesterday Tim posted about his attempt to fit 331 mm Hirsch brakes on a 2007 9-5. I got some additional information about this issue directly from Hirsch today.
Those 331 mm brakes were originally designed for the Troll and Saab Performance by Hirsch 2002 model versions. Since it was originally destined for those models and due to its size they it only be installed in combination with the Hirsch Performance 17″ or 18″ 6-spoke wheels. It looks like exactly that issue caused the problems for Tim and his friends when they tried to install it.
From model year 2006 on Hirsch offered the 345 mm brake for the 9-5 and 9-3 that fits the standard rims, too. This one could have been installed without problems. I got it in my 9-3x and I just love the performance it offers.
So if you are offered a Hirsch Performance brake kit for your 9-5 make sure to check the diameter to be sure if it really fits.