Overall walk-around of F-1 engine.
Picture 4 of 7.
Note the brackets for the thermal insulation leading from one set of propellant valves and over
the engine interface panel.
If you look very closely, you can see the engine's serial number, F-4023, stenciled on the thrust chamber, just forward
of the turbine exhaust duct and just clockwise of the drain tubes.
Also note the ID plates at the forward end
of the dolly.