Many thanks OP for this guide.
Tackled this today on my 2005 AXX with 74k on the clock.
Had a banjo bolt pump but used a 10mm ratchet spanner and taped up the m8 12 sided spline tool from my Hilka set (same as the machine mart set mentioned in an earlier reply) to the ratchet and worked a treat getting the bolt off and back on.
Be aware that the banjo fitting needs to be slightly lifted away from under the pump to free it as there is a lip on the pump allowing the banjo fitting to seat back onto the pump.
Case hardening was starting to wear through on the tappet so a wise move it was replaced now.
Also fitted a new o ring as the old one was brittle and had to be lifted off the pump with a flat head screwdriver.
Took 30 minutes start to finish.
Regards
Antony