Ken, I fully line EVERYTHING I make, so I just slot the exterior piece and install the clip and then use a dot of JB Weld
( an Epoxy) in the hole on my clips and when it's cured I install the lining. Fast and secure, never had one come loose. No rivet, no bump, no nothing, and no metal, rivet clip or otherwise, inside the sheath.
If you have access to a splitter you could split say 7/8 oz. and up in half, install the clip as above and then cement the splits back together.
If I was going unlined, I'd probably stitch a little "sleeve" on the back and install the clip in that, so as to keep all metal outside the sheath.
Paul