Final-drilled and dimpled #30 holes in forward tab of F873G-1 hinge support. Clecoed hinge support to firewall and top skin with spacer in place. Final-drilled #30 holes in hinge support and forward top baggage bulkhead. Final-drilled all #40 holes in top skin through firewall, bulkhead and instrument panel flange, baggage door support strips, hinge support and spacer. Marked and match-drilled F-8104-L/R forward skin support ribs. Removed top skin and all other parts. Ream #30 and #40 holes along bottom edges of top skin.