The Headwrap - Deleting and Editing:
It's all self explanatory. The files are located in tf/models/player/items/demo.  Each hat has 6 files, 18 in all. Simply delete all of them to remove the Turban completely or delete certain ones if you wish to use another hat.

Here is a list of the hat names, deleting 6 files with these names will remove the hat replacement for that hat.

Demo_Afro - The Demoman's Fro
Top_Hat - The Scottman's Stovepipe
Demo_Scott - Glengarry Bonnet