Right on both counts, Memphis.
I threaded them 10-32.
Originally the tangs were just peened down over some washers. I had to grind that off to remove the washers and the one remaining handle. I saved and re-used the old washers - nice patina already on them. Tang peened over washers is the same method I used on my home made drawknife.
With this one I envisioned dark red/brown handles from the beginning and I thought that brass cap nuts would go well with it. I guess I could have found some brass washers and peened the tang over those. But I like that fact that I can replace the handles again if necessary without doing any grinding next time.
I still need to hone the edge. I just wanted some pictures first because I like the patina'd look of the edge.