I have a 66 coup with many GT features, all original, but it's not really a GT. It has the stripes, emblems, exhaust trumpets, 140 speedometer and GT gas cap. It doesn't have the hi-po engine, extra headlights or tach. I'm really not sure what I have. The 5th Vin letter is A, so is that considered an A code Mustang? Tranny is a 3 speed manual with a floor shift. Also how do I know if it's an early 66? I've noticed some brake parts seem to be for an early one. Stuff like master cylinder needing 15/16" parts. I'm the second owner and have had it since 1974.