setting up a new USB drive?

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:
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.