1. With an SCP client,  WinSCP for example, download the contents of /var/customizations to your local machine.
2. Make copy of the index.html file and login.js and rename the file to an appropriate file name.  index-gridguard.html login-gridguard.js for example.  

Edit the index-gridguard.html file to update javascript reference filename. Changes have been highlighted in red..

1. Update the <FORM> tag's action attribute to the GridGuard URL. The GridGuard URL is https://<GGVA hostname>/gridguard/Start.  Changes have been highlighted in red.
2. Then an <INPUT> tag needs to be added inside the <FORM> tag. The <INPUT> tag name needs to be "realm" and the value needs to be the gridguard realm name that was created in Realm Setup.This value is case-sensitive. This addition is highlighted in light blue.

In the modified login-gridguard.js file you will need to comment out references to the password field since it needs to be removed.  Comment out the 'var passwd' line and the 'if (password == "") { block to disable the password field checking.  The changes are highlighted in pink.

Once the files are altered, upload the changed files back to the NetScaler / AGEE appliance.

After the files are uploaded open a shell command prompt session.  Now execute /nsconfig/nsafter.sh script. This will apply the changes to the login pages.

After all the customizations have been applied, this is what the new login page will look like.