Slow going this week but got back to about where I was with new parts and adequate edge distances. Got the old firewall brackets drilled out and removed. Installed new brackets and redrilled to the side channels. Paid more attention to the alignment this time and edge distances are all good. Twisted the new lower fuse channel on the right side and test fit with the skins in place. Still very difficult to get good edge distance. Opted to match drill the floor pan to the channel without the skin in place with minimal edge distance with the hope that it will pull in to place when riveting. Still not feeling great about the edge distance of that aft most hole on either side so opted to add an additional river between the last two. The floor pan attachment is not structural, but I'll feel better with an extra rivet.