Finished drilling the firewall to the F-770 side skins after measuring the firewall-to-skin distance several times. It’s difficult to get the required distance across the bottom of the fuse, but according to Vans it’s ok to move the bottom skin holes back a little. Sorry, no pictures of this area.

Even using recommended techniques for drilling holes in stainless (sharp bit, slow speed, lots of lube), I still had a couple of holes get egged out before I hit upon the idea of using my Brown Tool drill block to stablize the bit. Worked like a champ!