Z axis stabilising block STL file updated

These make a huge difference to the wobble on my printer.
Replaced original blocks with completely integrated blocks, both of the original Print-Rite blocks had cracks in them. New blocks were easy to do, and no fiddling required of the stepper driver.

With thanks to thedayowl, and Horror_18_m for the excellent original ideas.

Just in case anyone needed them, I have added the chain ends that I made for my setup to the STL's. Note also that there is a small clip in there to stop any droop