Yes, you could easily do that. The back piece covers everything including the silver rim around the front, but not the screen. The front piece covers the screen only. Thanks for your comments.If I wanted to use the back piece to protect the case, but not the front piece is that possible? The reason I ask is that I have the crystal film on mine already and I'm not sure I want to replace this piece. Does the back piece cover everything but the screen?
FYI, I bought and tried the invisibleshield. I've used it on an iPod and liked it but hated it on the iPhone. The fit on the back wasn't great, it felt like a rough edge around the volume keys and where the chrome part was, and the sticky grip make it terrible to try to get in and out of the dock.