basicly short shaft is 15in, long shaft 20in.
I have a 9.8 merc-- from top of mount to the tiller handle is 5in.
From bottom of boat to tiller 15+5 or 20+5. You can cheat your motor up,if need be. All motors measure different. Don't mount plate till get your motor.
Theres a chance either will work. Two things must happen , tiller is in comfortable possition , prop in the water.
you need to measure tramson. from bottom of boat to where you want tiller handle.
Now you have two choices short 20in [15+5] or long 25 [20+5].
witch fits you best.
WE can get this.