On the shaking the neck when playing vibrato, I noticed a few months back that SRV did it when I was watching a DVD.
Did he? I didn't know that. Wish my vibrato and tone was a good as his was 
So do I... I don't want to sound like him, but I want to know how to, so that I can use the bits I want.
I think it was the Live at the El Mocambo (spelling?) DVD that I spotted him doing the neck shaking thing.
On a good day I'm quite happy with my SRV approximations (and it doesn't need to be a strat through a fender-type amp folks - I'm reaching the conclusion that most of it is in the fingers...) - but there's a particular thing he did that I just can't get consistently (or accurately): on the first or second string, play 2 frets below the note you want, immediately bend up to pitch, and
then apply the massive vibrato, KEEPING IT IN TUNE...
Without watching him at the same time, he was so accurate with that vibrato, that you think he just played the note and applied vibrato - but it doesn't sound quite right if you do that. Watching film at the same time, it's the split second 2 fret bend up first... but if I do it I can't keep the note in tune!!
It was then that I noticed his whole arm and the neck of the guitar are going. I'm almost convinced that was how he did it, and I'm determined to master it!
Of course, even I do master it, stringing all the tricks together and playing at that intensity for more than say 2 bars at a time without snapping a finger - well that's another matter!