Im not an expert, so someone will correct me. I beleive they are a hlsd. There is no "way" in which they operate, but its similar to a 1 way. There are no clutches in it, only gears.
Ususally you do need the half shaft it came with, dont worry as they are strong (ever heard of a gtr snapping one?)
If you put the centre in your housing, with the halfshafts, and axles, you can retain the ratio you have now...(which is the other option i was looking at for my car -s13 ratio with gtr running gear)