Need to restore mailbox from a .edb file

We have an ex employee that we need some information about, but his mailbox was purged months ago and is not backed up on any of our current backups.  I ran a undelete utility and found a .edb and .stm files from last year that I can use to get his mailbox.  I have these files now, and I can't figure out how to access them in system manager.  I've looked through articles talking about mounting recovery stores, but things just aren't working, is there a special place I have to place the edb file?  I need this box urgently.