Torque Converter or Flywheel Test and Tune stand

I just put the motor on the test and tune stand today. I have a bell housing and was wondering if I could get away with bolting the torque converter to the flex plate so I could start the motor or should I use a flywheel? I have a neutral balanced flywheel that measures about 13" across. Any ideas??

Also what is the torque spec for the flex plate bolts?