Download SCV3 from here.
This will be a zip file, do not unzip. Place file on an SD card, USB flash drive, or in home directory on VIM2.
On the VIM2, go to Settings/More Settings/About device/System updates.
From the Update screen, under the UpdateLocale section, click Select.
The Update app will show you what files are available, something like, “OTA-Khadas.Vim2-SCV3-Beta.zip”.
Click the update file, the update app will return to it’s home page, from the UpdateLocale section, click Update.
Note: Do not select the options Wipe Data or Wipe Media…to be clear, do not use those options. After you click Update, the VIM2 will reboot and install the OTA update.
Again, please read superceleron’s post on SCV3 so you avoid any issues and you know what to expect.