Here is an example to get you started on the VBA side of things. I created a workbook that has two fields, Vendor and the File location. I also created a VBA sub procedure that will open the text file and replace any line that = the vendor number with a return carriage on the end of it and replace that with nothing (""):
Sub Remove_line_item()
Dim myFile As String, text As String, textline As String, posLat As Integer, posLong As Integer
myFile = Range("B2").Value
myFile = Application.GetOpenFilename()
Open myFile For Input As #1
Do Until EOF(1)
Line Input #1, textline
text = text & textline
Loop
text = Replace(text, Range("A2").Value & ChrW(14), "")
myFile.Write text
myFile.Close
End Sub
![enter image description here](https://cdn.statically.io/img/i.sstatic.net/3D2xb.png)
I only used one file path at a time but you could go one step further and go through all text files in a directory too. This could be a good start for you though hopefully.