With three prototypes down and hopefully only a couple more needed. On this third prototype I lengthened the hook so that the throw will be along the entire scale. I reduced the size of the faceplate so it would easily fit the case without post processing.
The next version I am going to try recessed tick-marks instead of the raised marks. During printing, being that the tick-marks are so small my printer creates a skew on the last layer that makes the tick-marks look slanted.
After I get a good basic model, determining the appropriate spring mechanism will be a bit of a challenge. I would prefer 3d printed springs but have not yet determined an implementation I like. This case allows for rubber bands or regular springs and that will likely be the first approach.