twin supercharging?
do you mean turbo charging?
IIRC the 1gge is a somewhat lower powered engine, and i think the parasitic losses from two superchargers would just kill the poor thing off.
twin turbo charging would be very expensive, and very complicated, i doubt youll end up happy with any kind of twin charging system, be it turbo or super or a mix of the two.
my advice would be to go single turbo or supercharger, and get it running reliably, then, and only then if you decide you want more juice, start looking at adding another turbo or supercharger.