excel function replace all letters in document with numbers automatically

bradpeterson just to poke my two cents in here,

I can see where the VBA code may trip up the importer, but if you use the first suggestion to have an "if" statement then I think that you can make that work.

Before you do this, are you importing data regularly or is this a one time event?  Will you have to repeat the 'clean up' each time?  If so, you might want to run this as a macro to record the building of the IF statement, the copy of the resulting column and the paste of the results - so you can have your raw data, run the macro and then import the data.

Just me thinking out of the box.