We did exam 38 with 3 Tendos and 3 Fire Mains (interrupting kisame and madara). 80 chakra was achieved from bani chakra and Asuma WB. Our powers - 110k, 90k, 90k, didn't even have Chikushodo and Shurado (for field buffs only Konan and Edo Hiruzen)... Water puppet took 10 rounds to kill though (close call).

Extreme seems a bit hard with our current power. Passed 4th and lacking damage (tried 2x Tendo, Gaara + Tendo etc.) in 5th...

For anyone struggling with EXTREME exam (before lvl 40):

Your opponents' HP scales with the lvl of standard exam of the team leader. I passed lvl 40 standard exam and enemies had over 50k HP. When I gave the lead to my teammate who passed lvl 20, enemies had barely over 30k HP. We did exams 1-20 in an hour retrying only against kisame with dodge+masked man (110+120k power) due to our non optimal play... So if you are stuck, just get someone who didn't finish normal exam, should be way easier.

This won't work with lvl 40, as you can't play the exam you didn't pass in normal mode.