Does the version of recovery-util on your device give you the option of exporting the userstore partition? If it does, download an update package for your device, transfer it over USB and reboot the device - this should take care of the main partition.
You can grab a copy of the diags partition from here:
https://www.mobileread.com/forums/sh...d.php?t=342535
The diags partition can be installed by flashing it over fastboot.