Hey guys just thought i would post this.
Once you send the 720/800mhz scripts to your pre, you don't have to use the quickinstall command line to install or uninstall them.
You can also use Terminus, just type the command in there and you can uninstall and install from your phone.
here are the commands:
sh /var/home/root/800MHzOS14.sh install
sh /var/home/root/800MHzOS14.sh uninstall
sh /var/home/root/720MHzOS14.sh install
sh /var/home/root/720MHzOS14.sh uninstall
It will install and uninstall and automatically restart the phone for you, make sure you write it exactly its case sensative.