Faking a time signature

[Menu Jacques]

Hello folks,

In a Canzon by Gabrieli, we have 4/2 time written as slashed C:

I tried:

  \once \override Score.TimeSignature.stencil = ##f
  \numericTimeSignature\time 2/2 | % 1
  \numericTimeSignature\time 4/2 | % 1

but this displays no time signature at all since both \time’s occur at the same point in time.

Thanks for your help!

JM