Well, it could look like this: (example: Fantastic Elastic)
Background Melody:
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-0-7-7-0-6-6-0-5-5-0-4-0-0-----------------
Melody A:
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-----9---9----------7---7-----7------------
--7----7---7-7---7----7---7-7----7---------
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--4-----4------------4-----4---------------
-----5----5-8--7--6-----5----5-4--5--6--7--
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-----------0--------0----------------------
--------2-----0--4-----2-------------------
-0-2-3-------------------------------------
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These are different parts of the song (I jumped over a few meldoies) and I recommend to make Melody A easier by using a capo on the 4th fret. Sorry, if the breaks are not that clear. My music skills are avarage.
Mod edit: Fixed alignment.