Turbo Sang did that before in his supercharged SGTI. to bad i've lost the article
and i don't think it's that straight forward since in the article did mentioned an extra ECU, water pump and four separate fuel injectors for this kind of mod.

inject methanol into throttle body? won't that cause detonation if the manifold temperature is too high?
the best way is direct injection into the cylinders through valve openings ala nitrus style.