Chosen Solution

Hi My 2014 MAC Mini is pre installed with single 512GB PCIe SSD, now it is almost full of space. I have spare SATA SSD 512GB which is now installed in my 2008 MBP, can I just remove from MBP and install it in Mac Mini?

Yes, you can move it over! You will need to follow this IFIXIT guide Mac mini Late 2014 Hard Drive Replacement and you’ll need a special cable Mac mini A1347 (Mid 2011-Late 2014) Upper SATA Cable which they are out of stock, here’s second source Mac Mini Upper Flex Cable