Place it in /Extra/Extensions folder or in /System/Library/Extensions folder.
If you have other card, change id in plist file of this kext.
P.S. You will still need EFI-string, EVOEnabler, ATY_Init or PC EFI V 10.3 bootloader (preferable) to recognize your card in system, but do not need to edit system kext after updates.
P.P.S. Changed osbundlerequired in this kext to load properly.