300E suspension strut question

What is the difference between the earlier model 86 and the 90's model for the W124 strut. I browsed partsbin.com site and they have different strut
for 86 and newer model.
My other question is the spring shim, what would be the effect if I replace the standard 23mm with an 8 mm shim.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.