Data Controls :: How To Delete Location Tag (Node) Programmatically Using Its Path In Web Config File

I want to delete location path using parameter textbox and allow user ..

example  :

location path = textbox1
allow user = textbox2

explanation : i enter name of location path in the texbox1 and allow user  in the texbox2,  when i click button delete then location path based on parameter textbox1 and textbox2 in web config will be remove..

this below my web config

<location path="3pm.aspx">
<system.web>
<authorization>
<allow users="testing1,testing2,tunggal ,usertest" />

[Code] ...

So far this is my code for deleting location path using parameter name of path , yet to parameter allow user ..

protected void DeleteLocationPath(object sender, EventArgs e)
{
string path = Server.MapPath("~/Web.Config");
XmlDocument xDoc = new XmlDocument();
xDoc.Load(path);

[Code] .....