Donna Lee is based on the chord changes to the (very old) standard called "Back Home Again In Indiana" . . . which is often just called "Indiana." The melody to Indiana is pentatonic and scalar and bass-friendly, so you might want to learn that melody first. Indiana is also in F, which is more bass-friendly than the Donna Lee changes in Ab.
Once you can walk, play the melody, and solo on Indiana in F, then see if you can transpose it to Ab. When you can play Indiana in Ab, then you are well on your way to playing over Donna Lee.
You can hear Christian McBride playing Indiana (arco solo) on a trio record with Gary Burton
here.
You can also make jokes about the bridge to Indiana (there is none . . .

)
John