This picture is from my 125 ( hydro drive )
I assembled the lift bar to lift plate and slide it in from the back. Bolts are 5/16-18NC and take a 1/2" wrench.
When I put the rear lift in
122 ( gear drive ), I had to disassemble the ratchet mechanism to get the plate in, then slide the lift bar and use the "universal adjective" to get the cotter pin in the hole.