Death Head (Main Riff) Chords

Hi this is the main riff of Death Head (Kaki King, Junior), so far as I know. I used a standard tunig, besides the first string (from E to Ab)
I didn't test another tunig, but there might be potential for improvement to speed up playing...

[ Tab from: http://www.guitartabs.cc/tabs/k/kaki_king/death_head_main_riff_crd.html ]
e |-------------------------------|-------------------------------|
B |-------------------------------|-------------------------------|
G |-------------------------------|-------------------------5-----|
D |-------------------------------|-----------------------6---6---|
A |-------------------8-8-6-6-8-8-|-------------------8-8-------8-|
Ab|-0-0-12-12-9-7-9-9-------------|-0-0-12-12-9-7-9-9-------------|

e |-------------------------------|-------------------------------|
B |-------------------------------|-------------------------------|
G |-------------------------------|-------------------------------|
D |-------------------------------|-------------------------------|
A |-------------------8-8-6-6-3-3-|-------------------------------|
Ab|-0-0-12-12-9-7-9-9-------------|-0-0-12-12-9-7-9-9-----7-9-9---|


Merso Manic