VI Import General Journal Entry


I'm trying to create a VI Import job to bring in some general journal entries but can't seem to figure out to grab the next Entry No automatically like I can with Batch Numbers and Invoice Numbers.  I can't get them to import properly without actually adding an Entry No column into my import file and setting something in it.  These are the fields I'm assigning and pulling from the data file.  Right now it's setup to pull that Entry No from the file, but I want it to not require that to be added to every file.  Any ideas?