Actually the one I got wasn't too bad. I just wrapped some 60 grit sanding paper around a paint brush handle and just sanded down the inside of the handle. Or just do a little filing around the end of the handle that's going in. Different ways, same results.
Getting the newer grinding bits helped. Getting it opened up to the 8mm mark means it was just a bit smaller than the smallest of the ferrules I measured.
Anyway - my dremel tool stuff is where I can get it; I'll see what I have left in the way of the tubes, and try to find the untouched rod to cut new ones.
@John Ruschmeyer - I do have a carbon fiber tube left cut to the right dimensions. As you have a bunch of different ends and ferrules, I suspect you can mix and match and find two that will fit the tube without having to do any more grinding/sanding.
