puttin it back together

[Bimmer335is]

Where do these go again?

[FredK]

Into the threaded bosses on that side of the engine.

Crap, I wish I had pics. But you thread a bolt through the knock sensor, and attach it to the block.

[PiercedE30]

make sure that where it attaches to doesn't have any paint on it, the knock sensor grounds to the block.