Slaughterhouse is solid technical Class IV that is primarily continuous. For some reason the actual names of the put-in and take-out aren't coming to mind. Where's my river log when I need it? It's an awesome run that I recommend.
Anyway, check this link, it's pretty accurate:
http://www.americanwhitewater.org/rivers/id/417
It is more difficult and technical than Numbers. The Rio Grande trail parallels most of this section of river. Scout Slaughterhouse Falls, you'll see the line toward river left. It's actually not a long walk from the put-in along the trail to Slaughterhouse. I've run this section between 750 and 900 and I think that's a good level for a first run. The lower the water the better chance you can get pinned though. I broached and was fortunate my head wasn't underwater when my boat got stuck. My partner was able to get out of his boat, swim over, and pull me and my boat off the rocks. Could've been bad so be careful.