Like Ed says, angling the thrustline actually equalizes the thrust.  With both motors turning CW when viewed from the rear, the right side of the prop gets a bigger bite.  On the left engine this is almost at the aircraft centerline so the left engine needs little if any out-thrust.  The right engine's thrust is being made mostly on the outside of the nacelle.  This gives it a LOT of leverage to pivot the nose to the left.  On the nose of the plane you'd use 3 degrees right thrust.  Out on the wing, you need a lot more to cancel the left-turning moment.  Ir counter-rotating props, which is why they exist. 

As I remember, The HB and some other motors have a bolted-on front section that can be rotated 90 degrees for reversing the rotation.  Looks funny, though.  The left motor should turn CW (when looking forwards with the plane) and the right motor should turn CCW. 

The brits tried the P-38 without counterrotating props and found it be a completely unsatisfactory airplane.