-Assembled and marked hole location for HS 405 & 404 ribs in the left HS. Removed the ribs and fluted them. Marked web centerlines and re-assembled on HS assembly. -Drilled aft attach holes for HS405 to HS603 for both left and right horizontal stabs. -Drilled match holes from skin to front spar both sides. -Did final marking of hole locations in HS405 after much study of the assembled configuration. Removed and drilled pilot holes in vise with wood block. Pretty confident I’ve got the edge margins under control. -Re-assembled HS 405 & 404 ribs and HS 710 & 714 angles back into left Horizontal Stab in preparation for drilling through holes in HS 405 rib, HS703 spar, HS710/714 angles, and HS404 rib. Checked access for drilling this out with the Sioux drill but decided to wait for my angle drill to show up (should be tomorrow) -Got the right Horizontal stab assembly back out. Assembled and marked hole location for HS 405 & 404 ribs. Removed the ribs and fluted them. Marked web centerlines and re-assembled on HS assembly. Played around with the HS405 fwd and aft flanges as I am still concerned about edge margin on the HS703 spar for the holes drilled through the skin. Called it night.
