I'v finally done it : 6820s Mountain Lion 10.8.5, Lion 10.7.5, Snow Leopard 10.6.8 full resolution and full QE/CI support ,files and small tutorial here for Lion and Snow Leopard and Mountain Lion.
I'm still testing some stuff on Mountain Lion and i'v started to write a full after install tutorial for full 10.8.2. and 10.7.5 6820s support with all the steps,and kexts.When i'm done with the testing,i'll upload
(10.9 tested,full QE/CI with some bugs,still figuring out how to fix them.
Resolution support is dropped because of radeonHD is 32bit only,dong said there isn't and wont be 64 bit,it compiles in 64bit but doesn't work for some reason,but there are other ways to add framebuffer(what makes resolution work) but they still don't show any sign of success with ati x1350/7196 1002 graphics.
So if any one can or has the time could your try dsdt method of injecting graphics card i will give everything needed for that method )
Edited: Sep. 7.