This info from FordEcat (electric catalog) reveals more about the S650 Mustang:
  1. S650 part numbers that are new start with "PR3Z"
  2. Ford is really weird about what has prices and what doesn't for the time being
  3. The fuel system is the exact same as the S550, so no larger fuel tank or anything
  4. All V8s have a dual cold air intake system (filters are not the same as the GT350/GT500/M1/Bullitt)
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  5. It looks like either all V8s have the GT500 cams, or none of them do, because there is only Left intake and exhaust, and right intake and exhaust, and they start with PR3Z
  6. The oil filter on the V8s are still in the same, terrible place
  7. The front underbody shield is now up to 4 parts, but even a base EcoBoost gets an oil pan shield now
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    (Dark Horse diagram shown)
  8. The connecting rods, engine block, and crankshaft have what looks like different parts for the GT and DH engines
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  9. Mufflers, resonator, and individual active exhaust parts can now be bought separate instead of having to buy the whole cat-back system
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  10. VDM is now mounted on the back of the trunk instead of under where the subwoofer would be
  11. We now have brake-by-wire
  12. There's mention of a DeurOS and Sync 4 in the infotainment parts, and different parts for each one
  13. If you get the reduced capacity amplifier, you will need to replace a lot more than just the amp to undo that
  14. A trailer towing module???
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  15. 6 taillight part numbers (PR3Z-13404/5-A/B/C), C seems to be the ones with the indicator at the bottom, A and B look the same? (no wiring info yet, can't tell)
  16. Mustang joins the list of Fords where the Gateway Module is no longer the thing with the OBD2 port, but it's now hidden behind the center stack
  17. Dedicated emergency call/SOS button
  18. Confirmed Dark Horse puddle lamps (looks like it might be US only? uncertain)
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  19. Seats in Black Onyx, Medium Space Grey, Medium Light Space Grey, Carmine, Harvest Bronze, Deep Indigo, and Bright Indigo
  20. Confirmed no heated/cooled functionality for Recaro seats (missing heating elements and blower assemblies)
  21. No more secret compartment for the owner's manual
  22. Unlikely unique Dark Horse keyfob
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  23. Different stripe designs for GT vs EcoBoost
  24. Transmission cooler moved in front of the radiator
  25. Stitching colors are Metal Grey, Gallery Grey, Race Red, Bright Indigo, Black
  26. New version of the MT-82? has new part number
  27. New version of the Tremec TR3160? has new part number too