Many thanks for your replies so far.
Lightman, I believe what you say may not be entirely right. I have official documentation from Bosch in Stuttgart, Germany, indicating that this pump is for 6BTA-A, 156. 0 kW, application "truck". The last three digits on the C series pumps is 856 instead of 846 on this one.
Interesting comment about the non-interchangeability between C and B series pumps, I did not know that.
Regards
Fridge