Like I said there are 2 kinds and I don't know which it is. One type rotates 1/4 turn then lifts out. The other unscrews to come out. If you get it wrong it breaks. YMMV I did find this which makes me think that the SSD is not the same on your model. optiplex 7760 aio teardown removal guide   [URL] Note: M.2 PCIe SSDs with capacities over 512G (512G/1TB/2TB) must be installed with a thermal pad. M.2 SATA SSD's and M.2 PCIe SSDs with 128G and 256G do not require a thermal pad.  I am not dell. I do not work for dell.  I do not have access to the PPID database or other service information. [URL] [IMAGE]   [IMAGE]  
Bought this desktop recently, which has 32GB Liteon M.2 ssd and 1TB toshiba regular 2.5" SATA drive. During the bios checkup, I can see that M.2 drive is configured under SATA section, but not M.2, after booting up, I can't see it under device management page (only that toshiba drive is listed), I tried to do clean windows installation through USB bootable drive, and I can't see this 32GB ssd either. Is there something wrong with it? And how should I get it visible and use it by windows? Thanks,
XPS 27 7760, 32GB M.2 SSD not recognized by Windows?