I figured this out in a few minutes, so it's not perfect yet. But it's a good start...
He's got the whole guitar dropped half a step (so Db, not D like a lotta Keller tunes).
[ Tab from: https://www.guitartabs.cc/tabs/k/keller_williams/restraint_crd.html ]
Then the chords are as follows... Keep in mind they're all relative to standard tuning,
while the first chord is played as an F#, it's actually a G... cool? Watch the video
he voices a lot of the chords in First position bar for his hammer on stuff
Verse
F# - A - B - Esus2
F# - A - B (crazy trill hammer on thing)
Pre Chorus is something like
c#m7 - B - A - B
Chorus is
F# - A - E
F# - A - B
c#m - A - B
or something like that. Sorry this was semi rushed. As I work it out more I'll post.
