Isco Ultra Star CA HD lens Disassembling  
Hi,  
I bought a 
Isco Ultra Star Ananmorphic Attachment HD Lens 
see foto.  
It got delivered in two parts: 
- Front Anamorph 
- Back  Lens 
- including screws  
Before i bought the lens the seller told me that i wouldn't need the back lens for the anamorphic effect, just the front and a taking lens. 
Saidly, I can't reach the seller anymore.  
Question: 
How do i use the anamorphic lens in front of my taking lens (Nikkor ai 1.4 50mm). 
I also bought a lens clamp. 
THe problem i have is that no matter what i do i can't get a sharp image through both lenses.  
Combination of anamorph front + back lens + taking lens gives me a sharp image 
but gives me a lot of vignetting and makes it pretty heavy.  
The back lens part measures 7.8cm. 
leaving an empty space of 7,8cm between ana and talking lens does not help.  
Camera in use nikon d300 crop factor 1.5  
any help much appreciated 
Big THX 
Edit Sorry image is out of focus will upload a sharper foto after work.