Great post!!! I have a 20" 2007 iMac that I am about to upgrade the x7900 core2extreme that I put in it a few years ago to a E8135 out of a 2008 iMac so I can install macOS Sierra.
Im also going to follow this guild to upgrade the wifi/BT card. This is the only post I have found about doing this on a 2007 model. So thank you.
Ill post pics of the cpu and wifi card swap if anybody wants to see them.
Thanks again,
Nandor690