How would one change the name of a custom property for all files in an assembly?

   I made a full assembly with a few hundred parts each of which have their own properties. I assigned part numbers and filled in the properties for each part using the default "PartNo" property as the title. However, my new BOM management tool looks for a property named "Part Number" otherwise it defaults to the filename. Is there any way I could change all of the "PartNo" titles to "Part Number" using a Macro or something like that? I need the filenames to have a description in them so I can't just change those to the part number alone.

   Thank you! 

SolidworksApi/macros