in reply to Re^3: What to do when converting Excel-supplied data to Unicode
in thread What to do when converting Excel-supplied data to Unicode

Nevermind. I determined that I should be using visual basic + the Microsoft Office Excel reference library to convert the files and then read them with Perl. Following suggestions from:
http://stackoverflow.com/questions/174446/how-to-automate-converting-excel-xls-files-to-excel-xml-fromat
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