I stumbled upon this---------------
Stevie used this guitar on MTV Unplugged. This guitar actually belonged to Stevie’s friend and personal assistant Timothy Duckworth. Timothy recalls that Stevie’s hands were so strong that he accidentally cracked the neck.
Guild produced the F412 model in the 1960s as a custom order-only, and it appears around 20 or so were produced during this time frame. These early models have some unique characteristics that differ from the later production version. One of most apparent differences is the tuners extend much higher on the headstock (above the Guild logo), and they are full size Grover tuners.
Other subtle differences include the "through" saddle as opposed to the later "drop-in" saddle and the older "G-shield" logo on the label.
This guitar was displayed at The Hard Rock Cafe in Dallas until its closing in 2019.
In April 2023 Heritage Auctions advertised an F-412 guitar, which they have stated was the one Stevie used on his MTV appearance. They stated that the guitar was hired from Studio Instrument Rentals in New York City, which contradicts every other source that the guitar belonged to Timothy Duckworth.
Guild F-412 12-string
Attachment 348560