I have my new site working ver 1.3.7, all products and data transfered from old version 1.2.4, but i need to now move the customers and address, but the tables are different.

Can i just upgrade the sql files from 1.2.4 to 1.3.7 using zc_installer? without damaging the 1.2.4 working site?

I do have a complete up to date backup if it goes wrong, but wanted info before I start

The 1.2.4 site is the live one at present, but a soon as the customers are transfered acrross the 1.3.7 will be live
thanks

or is there another way via phpmyadmin to alter the tables for a export to the new version

thanks

Andy