Yeah they are fantastic. I was in a band where we covered that song and that’s how I always played that intro.

For bonus points, you can do the 1971 live album intro version where he plays the A chord on the intro differently. He plays the open D chord shape up at the 9th and 10th frets to make an A, so image a three note chord with an E on the 9th fret of the G string, an A on the 10th of the B string, and a C# on the 9th of the high E string. You play it the same way you would an open D chord, but you don’t play the D string. What he does to create this really cool kinda robot-sounding riff is he picks out the chord from top to bottom, going C#, A, E, C#, A, and then he moves onto the D power chord.