I need some help on U-673 'flak-trap' boat.

I would like to know the number/position of support column(s) for the forward gun platform on U-673.

On site:
http://www.angelfire.com/co4/u_673/
the picture seems to show multiple columns supporting the forward gun platform. I cannot really tell the orientation, but there may be 2 side-by-side, or possibly 3 in a triangular formation?

However, other pictures (mostly from the side) and a 1:400 kit of U-673 show only a single support column.

Can anyone please help me?

Anyone?