Here's a link to a page with the lever blow up diagram. It appears that after the Lever Assembly (6) is removed by turning the Lever Fixing Bolt (9), that a #6 hex wrench (if I recall) inserted into the end and turned clockwise (It's a left hand thread from that direction) will loosen the Segment Assembly with Spring (4) and the whole thing should slide out. Here's the link:

https://www.flickr.com/photos/stronglight/5230303813/

I have a plan "B" if that doesn't work. I had a Suntour Bar end shifter where the Anchor Bolt (1) was stuck and would not budge. Got it out using plan B.