correct z bar for early a body SB 4spd

And here’s 3 pics of early A Z Bars:

First one is from an original 65 Barracuda 273 4 speed - 7.5 in - just pulled last week516077D4-624A-4BE8-99AE-82A5B26CE509.jpeg

Next one is from a 65 Valiant Slant 6 4 speed - 7.5 inches
9EB259D2-4679-4B52-A3A2-1FDDF6770170.jpeg

And the last one is from a 65 Dart GT 273 4 speed - also 7.5 inches CB58278F-D708-497D-BA1A-55380AEF8383.jpeg

Can’t say why your new one won’t work