Thanks nandor690 for the detailed info on the update.
I followed your instruction and upgraded my iMac mid2007 with a T9500 and new wifi/bluetooth module.
Everything works beautifully except that the "About This Mac" doesn't show the correct processor frequency.
I saw that you mention of adding the FakeSMC.kext sensor kext into /Library/Extensions and then rebuilt the cache with kext utility to show a correct idle speed of the CPU. Please kindly enlighten us on how to do that.