Because fitment, haha.
Just curious, why did you order those spring rates? That's pretty darn stiff in the rear, no? Might get a lot of oversteer with that setup.
No offence to you rar but do you guys really think having the spring right up against that plate is okay?? Any camber and the spring is coming at that thing on an angle. it wont be able to sit flat, only a small area of the spring will actually be in contact with the bottom of that plate, which means it could move around. Pretty sketchy. Has no one else noticed you kinda need upper spring perches to make this set up work properly??