The first thing you need to modified is the way you're thinking are. No matter how much mods you do on the boxster, if at the back of your head there's still that small voice saying "It's not a manly car"...you are going to be in a long ride of slippery mods
IMHO..quit hanging around to the forum or people that will say your car is not manly..hehehehehehe!
all the mods you have mentioned are pretty darn good. just the wheels alone could make a big difference and the rest could follow but the lowering part not really sure...
