This version of Autumn Leaves is performed in the low and middle register of the double bass. Just like with the level 1 version, the emphasis is placed solid swinging eighth notes. If your solo feels good, you can always build from there.
While this solo is labeled level 2, the only reason for this is that the range is limited to below thumb position. Bebop melodies played with solid swinging eight notes is the goal. Just listen to PC. He rarely plays above the F pitch on the G string.
Included is video demonstration, audio play-along, and complete notation.