Now you can go ahead and build this. Just a few things to keep in mind:

This might work with other dials with a ton of hacking, but the one I built this for is the older style Automatic Electric type 24 dial.  I'm not among the surprisingly large group of rotary phone enthusiasts so I'm not exactly sure what range of models Automatic Electric makes have the exact same measurements. 

Either way, once you have the dial you'll need to isolate the contactor arms by unscrewing the 4 screws holding them into the square riser, and moving around the little plates of insulator and metal tabs with screw holes to make them separate circuits. I had to make another insulator by just cutting a piece of cardstock (the kit comes with a bunch of extras.) I've messed with mine so many times I don't know how the were originally but that's one of the nice things with old stuff like this, it's pretty obvious what's going on when you see it. I'll take pictures when I assemble version 2 but this should be pretty straightforward. 

You'll also need this Nixie Power Supply Module which is expensive but these new tiny ones are great. 

I also haven't changed the code to work with the new version but it should be pretty simple to change it. I'll post that as soon as I get the boards.