Okay, gotcha... and agreed. The first document I attached at the beginning of this post was the installation guide from Hitachi. It's a short doc, but covers the handling of the drive. It also has the suggested mounting and the connector pinout. For my intended pocket-size all-in-one "wonderboard", this should fit the bill.
I also looked at SATA some time ago... found the same, no real documentation available for protocol, etc. I have found numerous SATA to IDE converters... they handle the protocol and hardware interface so it's basically transparent. In theory, one would expect it to work with a recent IDE BIOS that can support the extended 48-bit addressing. Here's one I found:
https://eshop.macsales.com/item/Addonic ... gLOhPD_BwE You can also find some very inexpensive ones if you head far east