Deburred & dimpled all components of L/H horizontal. stab. ready for riveting. Turns out that the -3 dimple die I was using was hitting the inside radius of the rib flange, so I had to sand down the shoulder a little on my disc sander. Didn't take much. Assembly of R/H horizontal stab. in process just need to match drill HS00005 & 6 to the spar & skin, plus the spar/doubler/ reinforcing angle holes outbd of the bend line. Once that's all done, it will be time to take this all apart again for deburring & dimpling.