Oil Filter
 

Update: I just installed the replacement adapter and gasket on my M3 2.3L eng. It took me all of 30 min to do so after putting the car on a lift. I now have a spin-on filter. I also enlarged the hole in the skid cover, making changing the spin-on filter a breeze for anyone. If any one wants more detail send a note. The adapter and gasket was bought from a local Madza dealer for a grand total of $32.46.