Of course that was N1051S which was owned by Pete McManus S/N 45-11371.
My best guess would be Sun and Fun 1981. History is at Case # 7.
"Silver Girl" is sadly, no longer with us. The aircraft was destroyed in a fatal crash in New York State in 1995. The Mustang in question is s/n 45-11371, c/n 124-48124, registered at the time your photo was taken as N1051S. It had served in Nicaragua as F.A.N. GN121, but was sold back into the U.S. in 1963. It was owned for a short while in the 1980s by Ed and Connie Bowlin. It was then sold to Jimmie McMillan, of Breckenridge, Texas, who rebuilt it as "Sunny VIII", the mount of Eighth Air Force ace Everett W. Stewart. The aircraft was sold to Myrick Aviation in England soon after the rebuild, but it came back to the U.S. in 1994. The new owner, George Krieger, died in the aircraft at an airshow after he stalled the aircraft on approach to land after a display flight.
Sully and Jim Church are regular contributors to this web site.
Thanks to both of you for your research.