I had a combination of carriage head bolts and screws to the ABS bumper cover and the aluminum under tray. It wound up breaking into three parts. The center peeled the aluminum undertray into a ball under the car and moving the oil cooler line into the alternator pully. The two corner stayed some what bolted on, except the drivers side finder liner was part of the aluminum ball, along with my unharmed wired transponder. Since I have to install a new bumper cover, I could bolt some mounts with break-away points onto the aluminum bumper bar, but was thinking of swiss cheesing the bar for nose weight reduction. What I want is something that's easy to replace, and doesn't take anything else (bumper cover, under-tray, or finder liners) out when it goes away.