Hello,
convention is blades are numbered as you would see them in 'rotation' as viewed from front looking aft, i.e. first blade to pass is #1, 2nd blade to pass is #2 etc. So for RR enignes with ACW rotation (when viewed from front) number in ACW direction. And North American engines with CW rotation (again when viewed from front) number in CW direction.
For Swedish Steve, it is most likely that you were sent with the engine shop distribution list. This document is where the blades are received for assy of the fan module in a box - with a piece of paper listing 1 - xx pn/sn. Then the blade weights are calculated and re-distributed by computer programme and a new list, or more commonly a new set of numbers are written in on the same sheet of paper next to the orignal 1 - xx numbers. I.e. #1 on original list may be now #14 position and #2 could be #8 and so on.
I have seen it happen a few times that blades have been fitted to the original 1 - xx blade order. This is not truly the fault of the line-engineer, as he would normally not refer to the shop document. The people who provide the list should 're-order' the blade positions on one list before sending out the work instruction.
For Dufo - RB211 data is generally IPS in the test-cell and converted to a/c units on-wing.
Regards,
N1 Vibes