This rig has come a long way!
Full floater rear axles became available on '93+ trucks in North America, HDJ81's had them from the word go in '90, not sure about other markets, all full floaters have rear disk brakes.
I think this is a semantics thing. I have always called the axles you mention semi-float, while an axle that has a separate drive flange a full-float (like the front axle). That's what we use on our landspeed truck, where the axle shafts simply have splines on both ends.
I was just about to comment how nice the FJ steelies look and lobby that you paint them white or light grey...then I got to your last post. Either way love the progress. Any plans to change the paint color?