You're going to have a blast!
I saw Willie many, many, many years ago, and I sorta expected it to be a ho-hum kind of concert. Imagine my surprise when it turned out to be an absolutely GREAT show. Really, really great.
I saw Dylan when he opened up for the Dead a long time ago (along with Tom Petty) and those shows were awesome, too.
Tell them both I said "hi!".