riff 1:C5 D5 D5 D5 x D5 D5 x C5 B5 A5 F5 G5
riff 2:C5 D5 D5 D5 x D5 D5 x C5 B5 A5 F5
riff 3:F5 G5 A5 C5 x D5 D5 C5 A5 C5 B5
riff 1
riff 2
riff 1
riff 2
D Am C G
riff 3
D Am C G
riff 3
riff 1
riff 2
riff 1
riff 2
D Am C G
riff 3
D Am C G
riff 3
riff 1
riff 2
riff 1
riff 2
C5
D5
E5
C5
riff 3
C5
riff 3
C5 x D5 D5 D5
D5
The main line riff fifths should be Em-form on the E A D strings. The D Am C G works well as open-form (imagine that! In a Neil Young song!). A nice high screaming 5th on a second guitar helps too.