I installed an ETD Quadrastep on my 5er for the same reason. I can tell you that it will require fabrication.
Based on your pics, I suggest you look at the one pictured below. It has a chance of giving you what you need and maintaining ground clearance.
If you need an installer, Interstate RV in LaGrange is recommended.
Photo Credit to JJD74.
The recipe for perpetual ignorance is:
Be satisfied with your opinions
and content with your knowledge.