Bilstein B4 REAR struct came with an tempered "ring". Needed?
 

Hi all

Two posts in a day. I am on a roll! :)

OK, so am installing Bilstein struts in the rear of my 99 base (product # 113320)

Two questions.

1) They came with 2 short and 2 longer bump stops. For the rear, should I use the small ones (the OEM had short ones).

2) On the 22-113320 strut "shaft", it came with a small tampered ring or washer, about 7mm thick (see attached pic). The old shocks did not have any. Should I remove it or keep it (the pictures on different sites show no "ring" for the rear struts , but rings for the front). The product # is on my struts so I know the one I have are the correct ones (#22-113320 = rear and #22-113313 for the front). I should add that when I tighten the nuts, the most I can do is that is sit flush with the shocks. When the old strut, I could tighten the bold more and see 3 treads.

Attached is a picture pointing to the ring I am referring to and that came with my B4 #22-113320 rear strut but this picture is of a front strut. So I am so confused. I know I have the correct parts, but why a "ring"? Should I just not use it? I already have a tempered washer that is much bigger...

Thank you!
IC