It got the better of me!
Quick note:
The plastic shielding between the fresnel lense and OHP glass is designed to route cold air in across it into the OHP. It may have a secondary function of preventing light bleeding. One end is open to the light though.
I found an old very thin tip soldering iron. Tracing the edge of the 'light stopping plastic', I cut out the offending material. The end result was fairly straight with a large amount of melted plastic left stuck to the OHP lid.
I chiselled it off carefully with a screwdriver and filed the edges flat.
The plastic could have been cut a bit further back but I decided to keep the air routers in place rather than chopping them out. Maybe the full screen width is available if I cut further. I might find out later
If you do this, please make sure you have a convenient gale blowing to get rid of the real bad smoke which seems to know just where your nose is!
The cutting process was very slow so be prepared to be in the smoky environment for some time. Fresh airflow is essential.
The result is magic!
I get nearly all the desktop. Everything from left to right is there up to the clock on the taskbar which I cannot see. Moving it slightly for games brings the missing Ammo into view
Many thanks Cesium
Photos to come of the massacre, may take a few weeks though.
Cant get them out of my camera!