If the internal routing is dedicated 1 to 1 and 2 to 2, in other words, there is an internal tube connecting them, I would run the front derailer in 2 and the rear in 1. If you can cross the housing inside the down tube, run the front into 1 and out 2, and the rear in 2 and out 1.
I run all my bikes right front. Right rear is a throw back to DT shifters, where you wanted to shift with your right hand but still have the most powerful brake accessible to the left.