I'm too confused right know. But at the moment I think Hitman's link was wrong, because target bearing and torpedo bearing were misunderstood.
Just by logical thinking I would return to what I said first:
only angle of bow and bearing dial were flipped:
The green/red dial background with "Bug links/rechts" is for angle of bow.
The green/red dial background without text is for bearing.
The black ones on the right (gyro) indicate the bearing of your torpedo when fired and are correct.
So it should like this:
But I'm not sure about it!