I think the confusion comes from the fact that what is commonly referred to as the SLH package has a number of options or stages, but centers around 10" brakes up front, with minivan calipers and mounts and disc brakes in back, with the vented 11" rear version being the pinnacle of that package. I believe it was presented this way because it was all stuff that could be bolted on to what was already there (ie knuckles) with no real modifications required.
Step up to 11" front rotors and now we need the whole knuckle assembly from the donor car, as well as the proportioning valve and an upgraded master cylinder (typically from the same car again). To add confusion to the list, many include the D-150 master cylinder as part of either of these packages and in doing so require adapters to connect the smaller lines of the car to the truck master.
It kind of comes down to just how bad---- do you really need your brakes to be? I'll likely end-up with a complete 11" set-up, but until I have time to re-due the whole front end, which I might as well do if I'm going to have the knuckles off, I'll be running the 10" fronts with minivan calipers and brackets, upgraded master, and solid disc read, pretty much as described on Dempsey Bowling's web page:
http://www.dempseybowling.com/ Give it a read, or if you're like me, give it a couple of reads, and it should become a little clearer. Just bear in mind that he's illustrating the many incremental upgrades that you could do, not just the baddest of the bad. Any way you go, you'll be Stopping Like Hell! (maybe the 11" version should be called SLH
S )
Hope this helps more than confuses!
Mike