I got another NED HTII which I have just finished rebuilding. I'm posting this because it is different than the other two HTIIs I've worked on. This created a temporary sense of disappointment when I realized it was different from my my spares. Having the spare parts was one of the main reasons I bought this reg!
This one's HP side has a raised volcano orifice, a flat, square brass poppet like USD, and a long HP pin. The other 6 Sportsways DH regs I've worked on have the Healthways type dished hard seat and plastic cone soft seat. Unfortunately, the seat on this different poppet was shot: deeply grooved and crumbling.
IMG_5388 by Vancetp, on Flickr
DSCF3386 by Vancetp, on Flickr
However, the first stage body is identical to the others, and I decided to try to install the NOS parts I had on hand. Aside from having to make a new HP pin, it worked perfectly.
Looking through my pictures of teardowns done on Sportsways regs, I saw that the balanced single hose first stages have a similar flat poppet.
DSCF3462 by Vancetp, on Flickr
Note the one piece balance chamber with the exposed o-ring. It is held in place by the plastic washer on the poppet assembly. Much easier than the o-ring buried in a groove the old style had. This is much like the improved USD setup. I thought this would be of interest.
The NED is done and works perfectly!