I beat the exam using the following configuration while I was level 53 with 9500 power. Guy, Neji, and Naruto are all 3 stars with max awakening and cultivation but were level 51.

Main Guy Neji
Naruto X X
X X X

Setup of main was lightning sealing slash, blade of light, chidori sharp spear, lightning enhancement, and shark summon.
First sealed itachi's skill then killed itachi in 2 turns. Then, focused on kisame and finished up the rest.
Hope that helps.