DTC’s ‘American Mariachi’ finally has an audience online. DTC and Stage West preserve live recordings of their most recent shows for viewing on the internet ARNOLD WAYNE JONES | Executive Editorjones@dallasvoice.com On the evening of Thursday, March 12, at two theaters on opposite sides of the Trinity River, two separate companies were putting up two separate plays that otherwise had little in common except their premiere week: American Mariachi at the Dallas Theater Center was working on its