@dab12ac First, please use the forum search system before opening a thread:About Nespi4case:
https://forum.recalbox.com/topic/24395/recalbox-v7-2-1-nespi4case-installation-tutorial About partition SHARE not visible:
You are not able to run Recalbox directly from the SSD because you are doing it wrong:
Rpi is not designed to boot the system other than from the SD card. You need to install Recalbox on your SD card, and use your SSD to store the ROMS/BIOS/saves/etc, just select the storage location from the Emulationstation menu.
Watch this video, it might be helpful: