That's exactly how I imagine it to work, but as the bars move with the lock bar, they will move on a slight angle. I'm thinking that the pivot points on the lock bar should be slotted to allow for this. I think I'll make roughly what I think will work, try it and then adjust to suit.
The monitor stopped working the other day - but I have found out with the help of a monitor expert that the degauss PTC had failed and made the fuse go short circuit. I removed the PTC and it now works again!
I have ordered a new one, as the colours are a bit off without a degauss in there.
Ladybug rules!