His instrumental stuff is his creative zenith for sure, as it really lets him show off his skills as composer, and his might as a guitarist, but still lets him experiment and do the crazy shit that he enjoyed doing. I will add though that I also enjoy his more straight forward rock and roll pieces too, but I'm just biased because that's the sort of stuff I was raised on. Good example of this is 'Camarillo Brillo' which is more streamlined, but still a little raunchy and humorous. And those trumpets that kick in for the last part of the song never get old. The only rock song I've seen do horns that good is Fleetwood Mac with 'Tusk.'