It cannot be done manually - it has to be done via software. You will need a USB cable and either ARC96 or Win96 to do it. These 2 wiki articles tell you how (for the Win96 article, go to the bottom) and also has links for each package's home or where you can buy it (anything blue is a link)
ARC96 - The RadioReference Wiki
Win96 - The RadioReference Wiki
and this article will tell you about the USB cable, and how to use Windoze Device Manager to check your connection...
Connecting scanners via USB - The RadioReference Wiki
However keep this basic rule in mind - you really don't need to reband your system *if* every freq in the trunked system has a '5' in the 4th decimal. If any of them have a '0', you will need the custom tables to track the system correctly