I recently installed a Nalbantov USB drive using an updated version of the insert and mount that I designed.
You can see based on the pictures below that the Nalbantov slim is slightly too small to fill the entire cavity left by the original floppy disk drive. Additionally, there are no mounts of any kind to hold the Nalbantov in place. This insert solves both problems: The drive screws into the insert at just the right distance and depth, and the insert also buffers the area around the outside of the drive.
I’ve included several pictures of how it fits into the case below. If you’d like to 3D print your own, I can provide the CAD file in 3mf format, gcode format, and STL format. If you’d prefer to order one from me, ready printed, you can order a Nalbantov Drive Bay Insert ready-made here.