A rest is out of place in polyphonic measure

[Kenward Vaughan]

Hello folks,

In a section of a piano piece, two polyphonic measures in the bass
stanza are tied together, with one "voice" requiring rests initially in
the first measure.  The code I've used to do this is as follows:

(time is 6/8)

<< {<c c'>2.~ }\stemDown\tieDown \\ { r4 r8 <g'' c>4.~ }\stemUp\tieUp>>
<< { <c,, c'>2. }\stemDown \\ { <g'' c>2. }\stemUp >>

The problem comes from the eighth rest in the first measure--it drops
down into the lower voice.  I had thought that something like an "s1"
in the lower voice would work, but that messed up everything.

My lilypond version is 2.4.5.

What can be done to keep that rest in the upper voice region of the
staff?  Many thanks for your thoughts!


Kenward
-- 
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