[bimmernupe]

Skiddy and txusa03,

Here are the pics. The 1st pic is how and where you seat the spring. Before trying to seat the spring make sure you have re-installed both metal rods. The 2nd and third pic is of the the plastic cog, sprocket, gear (whatever you want to call it for lack of a better term). Install the the platic cog before installing the new armrest. Place a folded card or paper of some kind to prevent it from falling into the the little hole there. If if does fall in you will need right-angle needle nose pliers or it is a beast to get out.
As you slide the new armrest in, kind of push to the right to get it past the cog. It will line up by itself with the teeth on the armrest.
The spring will require a little convincing to seat.