For a Weird Key Signature

[PMA]

Dear List,

I have a single clef (treble) with key signature consisting
of one Natural (on 2nd-line G) and one Sharp (on above-
the-staff G), as follows:

  \set Staff.keySignature = #`(((0 . 4) . ,NATURAL)
                                             ((1 . 4) . ,SHARP))

Unfortunately the PDF output displays these signs, not
vertically aligned, but with the lower (Natural) ca 1/8"
to the right.

How can I shift it "back" that far to the left for a vertical
alignment?

I have managed horizontal shifts, but not in the context
of a "keySignature" specification or its silently-printed
individual results.

Would welcome any thoughts.
Thanks,
Pete