Widebody Installation

Hello everyone. I'm new to the whole forums deal so please bear with me while I get the hang of this.

I recently bought a '05 BMW and I am currently working on getting a GTR widebody put onto it. So far everything is going well until I noticed that the plastic piece in the wheel well would have to be modified in order to work. It wont exactly come all the way to the edge of the new panel but it also sits lower than the new fender.

I also have an issue with the rear bumper from where the OEM fiberglass mounting bracket wont work with the new rear bumper? There is a support piece with the new bumper that is interfering with it so I am not exactly sure what steps I need to take to make it work.

I will work on getting some pictures of these issues and get them posted ASAP. If anyone has any suggestions or has even gone through the same issues I would greatly appreciate any help.