Alright have these on his characters:

Auto haste
Auto regen

Forget beating the game without those. Then, here are the party members you should use:

Zidane
Garnet/Eiko
Steiner
Vivi

Have Zidane attack and steal
Have Garnet heal and use summons, or have eiko use carbuncle, holy, and heal
Have steiner use shock the whole time (9999)
And equip reflectx2 on Vivi then cast Thundaga off of everyone because carbuncle casts reflect on the whole party. (9999)

There you go!