ur0: physical location on PS Vita PCH-1XXX or any Vita in general?

[eALduderino]

Hi guys, I had several issues setting up my SD2VITA. I finally made it. Still, I wondered where the actual physical location of the ur0/ mounting point is, especially on the (Fat) PCH-1xxx models, since they have no internal memory? I guess it must be hidden somewhere on ux0/ (first Vita-Memorycard and later SD-card after copying all the data from ux0 to the sd)? Is my assumption correct?

FYI:
I run Enso on 3.60 and all other HB-Software on the latest versions. For StorageMgr, this is v3.2 on April 8th, 2021.
I initially had the issue that the SD card wasn't recognized and/or with the SD2VITA inserted and that the system wanted me to format the Vita memory card. Canceling the request resulted in a boot-up without installed Data (homebrew and games) and the system not recognizing neither of the Storage media installed. I could narrow the issue down to two user errors I made during the setup process.
1st issue was formatting the SD card to exFAT with a cluster size above 32kB.
2nd issue was copying the files from ux0/ without hidden data made visible.

[Sekoree]

ur0 is the internal storage of the Vita, both Fat and Slim have 4GB of EMMC, on the Slim you just get access 1GB of that (which is unused on the Fat)
If you want that 1GB of internal space too, just use IMCUnlock and select the Default 2xxx option