You don't need to download any files in order to install Fantastico!
Just SSH to your server and enter following commands (you may also copy/paste):
cd /usr/local/cpanel/whostmgr/docroot/cgi
wget -N http://files.betaservant.com/files/free/fantastico_whm_admin.tgz
tar -xzpf fantastico_whm_admin.tgz
rm -rf fantastico_whm_admin.tgz
NOW GO TO YOUR WHM -> Add-Ons (Plugins on v11.x or higher) -> Fantastico De Luxe WHM Admin (scroll down the left menu).
Follow the on screen instructions.
If you get a Source Guardian error when you go to Fantastico for the first time, just run this command:
chmod -R 0755 /usr/local/cpanel/3rdparty/etc/ixed
Thats It.