this may help
Hey there beeny, looks as if you have missed removing the screw at the top the stepper motor bracket. I had the same problem. It is not visible unless you have a pencil neck and small head. (A engineers mirror on a stick works well though)
Attached are a few tips.
The PDF shows the stepper motor bracket removed to show where the hidded screw would reside. (don't confuse this with the upper resistor screw as I first did). there are 2 screws for the housing and another 2 for the resistor.
My ressitor was hot to touch, and required to be disconnected for a few minutes before removal
The second pdf shows a pic of the removed resistor and the soldered joints to fix. This worked with mine, and resolved the ongoing flat battery syndrome. This may work if the internal resister circuit is not already fried. In my case it was a dry solder joint, so all terminals were resoldered and extra solder was added to lessen the load on the failed connections.
As ususal, perform at your own risk and common sense...cheers