Yes, you would have to remove the air box, or cut out the bottom with the zzp intake, but for the k&n you're not supposed to. I wasn't saying you did your install wrong or anything, I was just giving the op other options because the install on the k&n is different than the zzp.You can do it without taking bumper off ... but i just found it easier to do that then to jack it up take the wheel and and fender wall off ... took like 10 min the first time i took the bumper off ... but to each his own
Also I have heard about people getting codes from too much oil on the K&N and it is only like 2.8"
The ZZP is a true 3" and requires no oil ... it also has a K&N filter and is $80 less
But again to each his own
EDIT: also I took my stock airbox out by only removing the radiator hose, power and ground cable and moving the master cylinder over but it was a pain would have much rather just took the 4 bolts out of TB and made it 10 times easier