I don't think you need a notch with the 4" coils. I have 4" coils to go in the rear of mine, but I haven't installed them yet. I read alot of threads on here, and I don't think you will need one. I'm sure someone who has this setup will chime in soon. There are a lot of em on here! Also, before anyone else does it I'm gonna do it for the first time!.... >>>
Sorry, I just had to...