Sharepoint: Changing Site Port

There are several ways to change a port of a web application in MOSS 2007, the easiest is as easy as performing two simple tasks:

1. Open Start>Control Panel>Administrative Tools and select Internet Information Services (IIS) Manager or simply hit Windows+R and type "inetmgr" and enter. Drill down inside the directory of IIS>[local computer name]>Web Sites>[Name of Sharepoint Site] and right-click on it and click Properties... and there you can see TCP Port, change it to a new port you desired (for example: from 91 to 27).
2. Open the Sharepoint Central Administration, go to the Operations Tab and click the Alternate access mappings (AAM) under Global Configuration. Click on [Name of Sharepoint Site]:91 and simply change it to [Name of Sharepoint Site]:27.

And you're done! Good luck, if you have any inquiries, please leave a message and I'll try to help you.