
These are the bulldog clips i'm talking about.
The clip I used had a handle that was roughly 65-70mm from tip to the hook that anchors it to the clip. I cut off one side about 35-40mm from the hook, and bent the end handle in a bit with pliers.
Not the most indepth explanation, but for it's worth, it works quite well, with a basic knowledge of mortice lock mechanisms. All you really need to keep in mind is that you need to push the hook up with enough tension to keep it in the groove when you turn it. I find depending on the type of lock, it may take a couple of circular motions (in the direction required, i.e clock/ counter clockwise) to pull the bolt all the way back into the lock body.
The extra bit that you cut off can be used as a lever lifter for the more higher grade locks, but i have a feeling that's for the advanced locks section

Thoughts / suggestions greatly appreciated.
I've got a picture of the finished product, can anyone host it? PM me for email.