3 hrs, 15 rivets
Spent more time than that, but it was mostly research and pondering.
Finished securing the parking brake cable.
Decided to drill a new hole for the vent line adel clamps. And then installed the nutplates. For that.
Drilled pilot holes for engine mount. Seems like such an important part, but the instructions just about say, "Get it about so, and then drill the holes".

Spent a bunch of time looking at how various electrical gadgets will attach to the firewall. Zeroed in on a location for the B&C ground plates, and the 60A ANL current limiter.