Trunk lid on 2002 E-320

I had the dealer adjust the height the trunk lid goes to when opened because I often hit my head when reaching in. I forget to raise it
further by hand first. :-(
Does anyone know how to raise it by some adjustment? How difficult would it be for a novice to make the adjustment?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload 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.