Only easier way is to have someone do it for you.
Here, this is tuned to MBA 6.2, so make sure you're using SMBios set to MacBook Air 6.2
Replace it to /Extra/Extensions and reboot
If the fan is still going like mad, then turn down Transparency. It's a hogger.
Go to preference, Accessibility, check 'Reduce Transparency'.
Turn off Notifications you don't use
Remove Widgets you don't use.
FakeSMC.MBA-6.2.zip