The engine's "master" ID plate. It reads
Rocket Engine Part Name: Rocket Engine Assembly Contract No.: NAS8-251256 Part No.: 104001 Spec No.: R-1420eS Stock No.: F-1 Serial No.: F-6045-1 Model No.: [blank] Accepted: [blank] Weight: [blank] Insp: [some sort of inspection stamp]
Below the "master" ID plate are two MD RD171-1052 identification plates.
This photo has been rotated 90 degrees counter-clockwise for readability.