One of those assemblies that might be easier to do than describe:
The inner wire of the cable slides into the hole in #48, and the brass screws #47 grip it in place, as mentioned. Alternate from one side to the other until snug. (You will want to assemble the plastic end piece before attaching it to the throttle handle.) The outer part of the cable also has to be anchored -- think the brass cylinder slips into a slot in the plastic housing, and is secured by the cover of the box.
The motor end is adjustable using the plastic adjusting wheel. The cable has to be anchored to the motor pan using assembly 25-27. To secure, the cable end needs to be held vertical between the “hooks”, then rotated into place with the wheel ahead of the clip. Put the control box throttle lever at the neutral detent, and adjust the cable length at the motor end using the adjustment wheel. When lined up, connect to arm of the throttle control gear and rotate the stainless clip in place to secure. The holes in the clip fit over the ends of the tube (#48 again). If it wants to slip off, increase tension by pinching the ends of the clip together slightly.