Can't say for sure on your 560, but on the 4.5 the pressure fitting was a 17mm, return line was clamped and mounting bolts were mostly 14mm, with an odd 13mm hidden behind the pump. Reservior was attached to the pump with a 14mm allen.
Hope this helps.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.