I've designed a book cover (attached) for a small publishing company and it seems I won't be able to print it as a single spot colour (Pantone 546C), as I'd hoped. So I'll be sending over the final artwork in CMYK instead(C-91 M-15 Y-0 K-83). As well as text for the Title, Authors, Biogs, etc. the cover will include a lino print which I can mask and fill in Photoshop with the same colour value.
My concern are the oft-spoken about registration issues with small text in CMYK. Should I be concerned at all? Or, since the colour is quite dark anyway, should I change the text to K-100 only and leave the lino image in colour. Or is there something I'm missing?