Go To A Specific Point In A File?

I have created a program in which I am supposed to add a stock to an existing table of stocks. I have this table of stocks stored in a file. The last line of the file is a ------- and the final stock is on the second to last line. HOw do I add a stock before the ----- and after the final stock??? I can't use append because that simply adds to the end and after the ---.

Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim sw As IO.StreamWriter = IO.File.CreateText("csvSTOCKS.TXT")
Dim sr As IO.StreamReader = IO.File.OpenText("TABLE.TXT")

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