I have a Koni/Eibach setup on the lowest perches and I didn't cut my bump stops. I haven't encounted a bottoming out problem yet and I've driven it hard and have hit some hard bumps/turns with 5 people in the car.
Nick, are you sure? hehehhe....... or maybe you've ridding at the bumpstop all the time? hehehe......... I experienced it before, because I didn't cut my bumpstop enough when I go with Ground Control/Koni setup, and I feel that the car is overly tight, like no bodyroll, no suspension travel at all. And true, I'm riding at the bumpstop, hehehee..................
But I don't know about you Nick, hahhaha!!!!!!!, just kidding.
Two big koni's go in rear and smaller ones on the front. You need to use some parts from factory struts for the front (the rear has 2 metal "plate" like things used to hold up the spring, the front you have to use your factory ones and can be removed with a rubber hammar).
The springs are labeled with numbers for front and back I believe and can be found on the instrutions. (the TIGHTER wrapped spring is for the front and the one with the bigger gap is for rear, if I remember right)
Your bumpstops will also have to be reused from your factory set-up, make sure they are not badly damaged or replace them like I did as they are just made of this cheap foam and over time the crack into little pieces which can get into your strut and cause you to rip the entire thing apart to clean it out (PAIN IN THE BUTT)
Don't cut if you want your shocks to last forever. If your don't cut your bumpstops upon installing Eibach + Koni, your you are basically riding on bumpstops, with no travel of shocks.
When I installed my Koni/Eibach, the shop did not cut it, so the ride was harsh. After 2 years, I took the suspension apart and discovered that there was no travel whatsoever. So I removed the bump stop and ride was awesome and steering becomes more predictable because of the absence of the bumpstops.
When I discovered that I was riding on bumpstops, instead of my Koni shocks, I immedately started working on cutting the bump stop. It was a painstaking process. I had to use a really sharp and small cissor to cut the dust boot, take it out, then penetrate the kinfe into the bumpstop. All done without remvoing the shocks and springs from the car........
Dang. I'll do that tomorrow when I take the shocks out to adjust them, but I bet that that is a huge part of my problem, cause it feels like I get NO travel whatsoever right now . Thanks for the help dude.