Re: V8 plastic Swap to V6??
The only installation differences between the GT bumper and the V6 bumper is the grill, and the wheel well liners. The GT grill and V6 grill are different sizes so you can't swap grills. There is a difference in size for the wheel well liners, you can make it work though. But everything else mounts the same.
One other difference, the foam under the cover is different too, but again it can be trimmed so that it works or you get the GT insert as part of the swap.