help with script to source data

I am trying to write a javascript code to be used in the Sales Order form.  The scenario is this -- I am creating a letter template to be created from the Sales Order.  The Sales Rep is mentioned in the letter, however, due to the way the system was set up and is used, all employees come out as Last Name, First Name in any outputs.  I created a custom transaction body field called Employee Full Name in the Sales Order record.  I also have a custom entity field tied to the Employee record called Employee Full Name (this