Hey guys, is there anyway to bring up the USB setup procedure again so I can set up a new larger USB drive without having to do a fresh install?
If your running the version of DietPi v120 or higher. Yep.
Its available in dietpi-software > userdata location: https://dietpi.com/forum/t/dietpi-software-user-data/400/1
Select USB drive to set one up.
Simply run dietpi-software and enter the User data location menu option. Once there, simply select the location you wish to use, or select Manual for a custom location. You can also setup a dedicated USB drive, if one is not currently installed.