340 torque converter question

Yes that is a lockup model and yes it works through hydraulics. You also need a lockup converter. A non lockup converter will not work. That is a V8 trans btw. The term TF6 is somewhat confusing because originally the TF6 was made to only fit a 6 cyl engine. Later they recast the bellhousing on the TF6 to fit a small block V8 but still called it a TF6 which the old timers like me and Kim know as a 6 cyl trans.

If your 71 340 is original it is an internally balanced engine