I have the K-Mac on the rear and all four collision bolts on the front with Voughtland springs and koni shocks. a couple of things I found. Getting the old bushings out was almost impossible. The took the K-Mac comes with could not remove them. I ended up using a press to remove the inner steel bushing and the rubber. I then had to notch the out steel sleeve with a saws all to get them out. I hope you don't have this problem on the front. another issue I had was that I didn't have my stock shocks to reuse the dust covers. I called Koni and they said there was no need for them. Installing them without sleeves revealed that on the front, I was almost on the bump stop, I cut about 60% off the fron bump stops and about the same on the rear. An yes I had the Koni's for a lowered car. My car rides great, and handles even better. the alignment shop was able to dial in the rear perfect and the front was right on the money as well. Since doing the work, I have replaced my tires. All four tires wore out pefectly even. I now an running BFG KD's in 235 40 18 front and 275 40 18 rear. I was running 265 40 18 in the rear up until a couple of days ago.