64 Dart Gt 4 speed won’t shift into gear ??

Hi guys, I have a 1964 dart Gt 225 4 speed manual. I put in a new clutch, pressure plate, push baring( the clutch kit) and with a rebuild trans and now I can’t shift into gears when the cars is running. I’ve already adjusted the pedal linkage and the shift linkage and still no luck. I have adjusted the pressure plate and clutch as well and made sure the clutch was installed correctly. When the car is on I can’t shift and only grinds hard if I try to put in reverse or another gear with clutch pushed in but when it’s off I can shift freely to any gear. I’ve looked at all over the internet and tried all the different suggestions but still no luck. Thanks if any one can help.