Hi Ken,
Thanks for the advice. The FQDN is still being set up, but I was able to access the site externally after modifying the IP in the config.php. After reading through some other posts here on the forum I know that this isn't a permanent solution and plan to swap the wwwroot over to the FQDN once it's set up.
Thanks for you help, you were able to point me in the right direction on this one. Much appreciated!