Jimi and Eric, that is very much what I have been trying to to. I started a couple years ago in lessons playing the main pentatonic position, and expanding one position up, and one down so I had some slides to go to etc., and also focusing on the barre chords that fit in that main position. I have since learned the shapes of the pentatonic patterns all up and down the fretboard, and can transpose for any key. I am not automatic at it, but can get there as long as I am a bit familiar with the song. I have lately been trying to use those same pentatonic shapes, but the major scale versions, so I can do the same thing.

It is a little new, since a lot of the songs I have played over the last few years are more minor or blues based. Focusing on the chords (and knowing where I am in the song of course) will be a big help as I familiarize myself some more. As I learn this, I anticipate I will add in the notes that fill the gaps, and in that way, pretty soon I will have decent knowledge of the entire major scales. I also love to combine the positions so I can slide into notes rather than stay in the box, and get different sounds that way.

But I think focusing on the chords, and little licks that use the triads, transpose and use the same notes elsewhere, find cool passing tones, etc., is key. Without that, it is easy for it to degenerate into noodling. That works ok on "Wooden Ships" as that is pretty much what Stills did on that song anyway, but most of the songs need a bit more focus. Fortunately my ear anticipates and follows the chord changes a bit naturally, so at least I have that going for me.

I also am going to continue to learn the key licks on some of the cover tunes, both to identify the song and give a starting place, and also to learn vocabulary, and how other guitarists have used the available notes.