Thanks to 90LX_Notch here who gave me much advice offline on how to use and rezero my Starrett 12-258 Digi-Chek Height Gage when the micrometer, digital counter and gage heights didn't match. I took copious photos during the troubleshooting and repair and put together a tutorial on how this was done. I uploaded it to the Metalworking Dropbox. It is titled "Starrett Digi-Chek Height Gage - Disassembly, Trouble Shooting and Zeroing of Starrett 12-258 Digi-Chek Height Gage." The file can be found here:
As of this posting the text file describing the tutorial has been accepted. Since the tutorial itself is almost 4 Mb, it apparently will require human review before it's accepted there. I don't log onto the forums regularly, but I do have this topic set to send me notifications of subsequent posts to this thread, so if you have questions, or the tutorial isn't accepted because of size, post here and I *should* receive notification. Please try the dropbox for the file first though. Of minor interest is a description of the materials and method I used to repaint some of the missing digits on the counter.