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)
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
One thing I forgot to mention - no custom tables are needed if the system is a true P25 type - the scanner will handle it all from the data on the control channel...Mike