Not sure if this is the right category to submit documentation, but here is at long last, the Magnavox Manual 8517, which is actually a full-blown service manual which includes the jumper settings, all FDDs options, all HDD options, all CD-ROM options (if it was a CD model), schematics and etc. I've had this for several years.

This covers the following models:
  • HeadStart 286 (HS1200), 286CD (HS48CD), SX (HS1600), SX CD (HS64CD)
  • Magnavox 386SX (MGP160), 386SXCD (SR16CD)
  • Magnum 286 (MG1200), 286CD (MG48CD), 286SX (MG1600), 286SX CD (MG64CD)
  • MaxStation 286 (MX1200), 286CD (MX48CD), 386SX (MX1600, typo shows as MG1600), 386SX CD (MX64CD)
  • Professional 286 (PR1200), 286CD (PR48CD), 386SX (PR1600), 386SXCD (PR64CD)

    All have a "GY01" model suffix.

Here's a quick scan from my phone, once I find my scanner, I will update the link with it: