Gawd, I hope that it takes a 36mm socket because that's what I've been using on my e32/e34/e38/e39 over the last couple of decades. Granted...those models oil filter reservoir was top side and doesn't have the inner 6mm drain/screw plug...but the larger "hex" appears to be the same size on these models as the X5's. Im only 2 months into e53 ownership...so haven't had the chance to check this out any further...hopefully the DIY'ers will chime in:
The diagram at bmwfans.info &
maximillian importing company is drawn better and you can see that there's a connecting line for item
#4 (oil filter cover) to
the gasket, #5, & #6...which means that all these parts are included with item #4.