A 63 1/2 Mustang? A top load T10?
Talk out your ass much?
The Mustang was a mid year introduction in 1964… there were 64 1/2 Mustangs, but the only thing released in 63 was a concept car. There was a 260 available in the 64 1/2's (that's about the only thing you got right) but the 4 speed toploader was a FoMoCo built transmission that replaced the Borg Warner T10's from about '63 into the early 70's.
Try doing your own research before regaling us with your verbal diarrhea.