I started reading because I have similar, though probably less than your, pull to the left with my Hankook V12s. Then I kept reading and sound like you still have it without them. I'm subscribed out of interest. Hope it works out.
MODS: JB4 Rev 3 ISO, AFE CAI, Berk Street Exhaust, BMS Catless Downpipes, Hotchkiss Front Sway Bar, M3 Front Upper and Lower Control Arms, Koni FSDs with Eibach Springs