JonOchsner
Blues Newbie
Are the finger positions correct on page 42 of CRGU for the E5?
Yes.
Since this is an open E in the diagram you can play the 6th string root open and the 5th and root octave with 1 finger.
Some think of the power chord as just the Root on 6th string and 5th on next string. Griff is also adding the root on the 4th string. It's still just the Root (doubled) and the 5th. No 3rd.
So moving up and down the neck you would use your 1st finger on the 6th string root, your 3rd finger on the 5th string two frets up and your pinky tucked in under your 3rd finger on the 4th string at the same fret.
(It's actually like an Em shape barre chord without the upper 3 strings.)
Although some will finger this differently.
For example, play the root with the 1st finger and barre the 5th and 4th strings with their 3rd or even 4th finger.