A903 3 speed to a833 od

Can anybody help me finding out how Many splines The output has on a 903 transmission.

I have ordered a 26/30 spline a833 od and I’m worried that it won’t fit with the 30 splines output.

I’m quit new in this area so any help or advise will be much appreciated.

My car is a 65 dart 170 slant six 3 speed 903.


Thank you

Have you swapped over to the 4 spd OD yet?