Again, I'm grateful for the suggestion. Didn't find how to do it.
From the clover screen, if I press space bar, I see
Volume size: 237655Mb
(check mark)PciRoot(0x0)\Pci(0x17,0x0)\Sata(0x5,0xFFFF,0x0)\HD(2,GPT,0FA2219C-AFAD-46AE-8DE6-0941F4BDEB07,0x64028,0x1D02BA00)\System\Library (the rest is...