I Blame CHIP FOOSE he's making me crazy

You're using air and 20's right? Biggest issue you will have is tire diameter when using 20's, both front and back, depending on sidewall of course. When mine will be deflated, I'll be at 2 inches to the rocker and will have about 1/2" from the fender mounting flange and the tire. If you haven't ordered your shocks yet, you might want to connect with RideTech and talk through it with them, maybe they can make a shock length recommendation to get what you want. Before you do any cutting, pull the shocks and springs and drop the car down to your "slam" (with wheels/tires on of course), see what you have for clearance on the fender so you know what work needs to be done there, but also measure to the shock mounts in the front & rear. Then do the same at ride height. This will give you an idea of shock length needed to get where you want with stock mounting locations. You may have to relocate shock mounts up front in order to get the proper length shock in there. Rob channeled his Alter-k into the frame rails in order to get the stance he wanted, that may be something to look into for yourself as well. You're biggest issue regardless, I suspect, will be the mounting flange on the fender itself. If you're bulding custom inners, those are not an issue, but the flange on the fender could be.