Correct p/n for dealer shocks
 

I'm looking to replace the shocks on my '87 300D. I understand MB has had several different part numbers for shocks. Some rear shocks I see have "1" on them and some have a "2".

I'm interested in getting dealer parts, and am wondering which p/n I need to get. What's the difference between the "1" and "2". My '87 300D parts car has "1" on the rears as do MANY 300E's that I see, while my daily driver has "2" on it...

Thanks,
Brian