Replacing characters

[Mark Allen <mallen@xxxxxxxx>]

I've got a physical file (actually copy of a spool file) containing phone
#'s in format xxx-xxx-xxxx.  I need to send this to a software vendor but
for privacy reasons I need to change all the phone #'s to "fictitous"
numbers i.e. change 706-678-9565 to 945-224-4848 or such.  The phone numbers
start in a various # of places in the file (i.e. some might start in
position 33 others 55, 87 etc.) I've been racking my brain for a quick and
dirty way to this without having to manually edit the file.  Any ideas from
some of you genius' out there?
 
Mark Allen
IS Manager
Wilkes Telephone & Electric
11 W. Court Street
Washington, GA 30673
Phone: (706) 678-9565
Fax: (706) 678-1000