TaoTao 150cc Quantum - Bolt Sizes

[cantstopwontstop]

Hi,

I'm replacing the exhaust studs and nuts for my TaoTao 150cc Quantum scooter, because they broke off.

I need to take off the exhaust pipe and/or muffler. I bought a set of tools but I still don't have the correct size pieces. Can anyone tell me what size power drill pieces I need to get to remove these bolts? The wrenches that came with scooter don't fit these sizes either. I have to remove these bolts to remove the exhaust so I can drill out the broken studs and replace them.

Thanks.