Iphone 4 Missing power button bracket??

New guy into my first phone. Iphone 4 with non-working power button. Lived with it but bought new button and new proximity cable. Installed and acts just like old one. No button travel what so ever. My question is the install guide talks about transferring a power button bracket over from the old flex cable to the new one. What I took out of the phone and the new one I had in hand are identical. There was no "bracket" to transfer over.
Am I missing a part? Is this why the button just locks up and will not move?
thanks for your help