OK.. lets try this again. If you put it on 180 degress the wrong way.. YES it will still spin freely but NO it will not sit flush with the head, due to the fact that the shape of the portion that you are sticking into the head is shaped so that it only truly fits perfect, 1 way.

& due to the fact that it would not be flush & you were cranking the car with the pressure of the mounting bolts pushing on it.. it sure as hell would put stress on the 2 nubs that u riped off!

Hope thats a lil more clear!

if it was properly mounted then it would distribute the pressure on the 2 nubs evenly.. if it was put on 180 the wrong way.. it would put all the pressure on a certain point of the nubs.. causing them to give