Do you want to print by the press in the first pass only C and M?
Then compare the result with the proof print, using only C and M?
If so, then rasterize the PDF by Photoshop in CMYK mode, using
the correct CMYK profile, with sufficiently high resolution, in order
not to make the text fuzzy. Then uncheck (switch off) the channels
Y and K and print.
I'm having some doubts, whether this will deliver good results.
Proof printing requires fully calibrated inkjets and appropriate
software. Never mind, the mentioned workflow will probably show
whether the separation is correct by principle. But this becomes
obvious anyway by switching channels On/Off in Photoshop,
or, more professional, by Print Production > Output Preview in
Best regards --Gernot Hoffmann