Reply To: Inch symbols (double prime) being changed to quotation marks!

Oh absolutely. The magic GREP code to search for one out of a set of characters is [this] — every single character between the square brackets. [this], for example, will find either a single 't', 'h', 'i', or 's', and [that] will find a single 't', 'h', or 'a' (the duplicate 't' is ignored).

This GREP search will find either a straight single quote or a single curly one, and only when preceded by a digit:

(?<=\d)[~'~]]

and you can find its twinned brothers using

(?<=\d)[~”~}]