I've finally had a few hours to play with the Switec steppers.

They're pretty cool little things. Guy Carpenter has published an Arduino library for driving them. They only pull 30mA/coil so can be driven directly from the Arduino. For a permanent solution though, some protection diodes should probably be thrown in.

As a first test, I deconstructed one of my other gauges and stuck one of the steppers on the back of the face. A bit of tweaking and a bit of superglue and I have it all stuck together nicely.

Loading up an Uno with Guy's example script, fiddled around getting the right wires connected to the right pins and it works very well. As you'd expect with a stepper, repeatability is perfect.