Gröner mentions in the text, that the position of the tubes could be changed.
The pictures that I have only show the tubes in the aft position, though I have to say, that the forward position is somewhat obscured in them.
Maybe sometimes two sets were carried?
In the drawing, I decided to show the forward mounting position and install the aft set.
I might do a camoed version sometime.
Edit: Garlic was faster, thanks!