Diagram showing the orientation of the S-IC's fins with respect to vehicle position. Referring to the second diagram, we see that, left to right, the visible engines are 102, 105, and 103.

Click image for a 2097x1637 pixel version of this image in a new window.
Adapted from p. ix of the F-1 Engine Data Manual (R-3896-1), located in the archives of the U.S. Space & Rocket Center. Formerly available from the NASA Technical Report Server.
Scan and adaptation by heroicrelics.

Diagram showing the orientation of the S-IC's engines with respect to vehicle position. The engine numbering is basically the same as that of the S-II stage:

Click image for a 2097x1914 pixel version of this image in a new window.
Adapted from p. ix of the F-1 Engine Data Manual (R-3896-1), located in the archives of the U.S. Space & Rocket Center. Formerly available from the NASA Technical Report Server.
Scan and adaptation by heroicrelics.