Tower Plus EBT2250, support dual sided SSD? Will an 8TB dual sided SSD work?

On many models of Dell desktops, Dell designs the usage of thermal pad to apply between underneath the M.2 NVMe drives and the PCB surface of system board.  The thermal pad thickness can be up to 5mm.

Therefore, I would say YES to your question.  The Tower Plus EBT2250 will support dual sided solid state drives.

Just to give a feedback. Removed the factory SDD and installed the 8Tb WB SN850x. It now works perfectly as the primary drive of the Dell EBT2250.

Something odd: it was only recognized with the Dell OS Recovery Tool. Trying to install Windows with a pendrive created with Microsoft Media Creation tool or Rufus simply did not work. The drive is not recognized by the Windows installation system except with the Dell OS Recovery Tool. Is there a workaround for this since I prefer to have a clean Windows installation?? Are there drivers I have to add to the "clean" Windows image in order for it to see the new drive?

You can go to Dell support site and download Intel RST driver for your system.  Double click to run the downloaded file, then select EXTRACT (not INSTALL).  Put the extracted contains into a folder and copy that RST driver folder in a USB drive to use it during Windows installation.

At the installation screen whereas the SSD drive is not recognized, select load driver and browse to the RST folder.  Select the RST drive to install and all your HDD/SSD will appear for selection.  In your case, directory similar like this:  X:\RST\production\Windows10-x64\19041\Drivers\VMD