first you will need secure nuts and bolts, not zip ties. second, you need to bend your core support UP... and lastly if your trying to get the bumper to sit flat against the fender, it just wont happen without alot of modding because from the factory they come with a special plastic anchor that spaces the bumper about 1/8th an inch.

and Certifit and Egay parts fit just fine if installation and fitment is done properly...