For the bumper foam I just cut the bottom half of it off. It does still support the bumper and do what its supposed to. For the under tray on the bottom I pried off that little flap on the bottom of it with a razor and trimmed most the the front of it off to fit. Then I drilled four holes through the splitter and the tray to secure it down. Im really happy with how it turned out, only thing I need now is a GT500 radiator shroud and my bumper back from paint and I will be set. I did my swap with paint for under $1500