guitar one = 4 times
|-RIFF-C------------|
|-------------------|
|-------------------|
|-------------------|
|-------57788-------|
|-5h8p5-------6h9p6-|

so Rob, you play this riff 4 times, then you jump back you Riff A right?

the last time you play that riff C, the notes goes this way...

|-RIFF-C------------|
|-------------------|
|-------------------|----the last time...
|-------------------|
|-------57788-------|
|-5h8p5-------5h6p5-|

thats it!  take a look bro!