miele g660 premier & bosch sgs43a42uk/01 dishwashers

hi guys,

2 queries regarding dishwashers:

Miele Model G660 Premier: I need to identify the boss and screw that retain the upper (above the basket in ceiling of dishwasher)spray arm in place I think the part no. for the spray arm is:6117370 but does not appear to come with these parts?

also some of the newer Bosch dishwashers ie:SGS43A42UK/01 have a magnetic float in the base and a reed switch mounted on a pcb on the outside of the plastic base this seems to be how it registers the correct level of water?
the well the magnetic float sits in gets stuck up with grease or bits which upset the level detection. I heard that there is a modification but the bosch site makes no mention of this & the part numbers do not change anybody out there no of problems with this set-up and if there is some kind of modification.

cheers