I Should Have Known It Tom Petty and the Heartbreakers Tom Petty & the Heartbreakers, Mojo - June 2010 - Track 7 submitted by Greg B. Tuning: standard Chord Definitions: C6 = xx5555 B6 = xx4444 Bb6= xx3333 repeated lick. the "G" riff {sot e|------------------------------------------------------------| B|------------------------------------------------------------| G|------------------0--3b--0--------------------0-------------| D|-------------0--3------------------------0--3--- (guitaretab.com)