Shifting problems

[bmx1080z]

Hello everyone, I am trying to work in improving the shifting of a car. Our goal is to make the shifting smoother but at the same time reduce the throw. Currently it has a motorcycle engine and transmission and the shifting using the paddle shifters causes too much fatigue in the racers hands. We were trying to engineer a piece to attach on to the transmission axel. If there are any ideas or solutions let me know.

Thanks!