Watch the Rockabilly Funeral online guitar lesson by Bill Kirchen from 30 Hot Rod Guitar Licks You MUST Know
This lick calls out for tremolo. They call it vibrato on Fender amps, but it's actually tremolo. No matter, it sounds so good they can call it what they want. Very few notes here, there's octave 1's and a 5 in each of the 3 chords. That's it. Maybe a few 7's. Channel Bo Diddley - there was but one.