I would side with Randy's remarks, personally. I think he seems to have his head screwed on straight (not to say that others are entirely off the mark - just off the track a bit maybe). Why make life difficult, if not impossible for yourself, Kirk? What I would suggest is getting hold of their printer and ask them if you can provide them with the RGBs directly - and if THEY could do the conversion (hopefully with your consent - if you can see a test). It's their business afterall - and they're fully set up for it. Why futz with things you can't control - especially if your work is going out to multiple printers frequently?