After running the StackScript I loaded the install.php page. I was greeted with the following error:

Failed to connect to your MySQL database server. MySQL reports the following message: Access denied for user 'username'@'localhost' (using password: YES).

Are you sure you have the correct username and password?
Are you sure that you have typed the correct database hostname?
Are you sure that the database server is running?

For more help, see the Installation and upgrading handbook. If you are unsure what these terms mean you should probably contact your hosting provider.

I logged into the linode and checked the sites/default/settings.php file and noticed that my password had an @ symbol in it. This was causing the problem. The StackScript needs to provide a properly URLencoded password for the settings.php.

I then tried to run mysql client from the command line on the linode. However, I could not log in either. So it appeared that the mysql password wasn't set correctly either. Does the mysql password also need to be encoded/escaped? Needless to say, I simply reran the StackScript again and removed the @ symbol from my password and it all worked fine.