'64-1/2
There are subtle differences between the early '65 ('64-1/2) and later years. The photos and captions explain.
 The A dimension on the right-hand...  The A dimension on the right-hand side for the '64-1/2 from the upper beltline radius to the top of the MUSTANG emblem is 8-7/8 inches. |  The B dimension on the right-hand...  The B dimension on the right-hand side for the '64-1/2 is exactly 7 inches from the fender's trailing edge to the left-hand side of the M. |  The Pony and Tri-bar emblem...  The Pony and Tri-bar emblem C dimension on the right side for the '64-1/2 is exactly 7 inches from the upper beltline radius. |
 From the right-hand fender's...  From the right-hand fender's trailing edge, the Pony and Tri-bar emblem D dimension is exactly 12-5/8 inches. |  When we move to the left side,...  When we move to the left side, the measurements are practically the same, with the Pony and Tri-bar emblem C dimension exactly 7 inches from the upper beltline radius. The MUSTANG A dimension is 8-7/8 inches from the upper beltline--identical to the right side. |  As with the right side, the...  As with the right side, the left side is dimensionally the same from the fender's trailing edge forward. MUSTANG B dimension is exactly 7 inches from the trailing edge. The Tri-bar emblem D dimension is exactly 12-5/8 inches. |