Why not just de-solder the ribbon cable and solder your own wires on? Might be easier.
I suggested leaving the cable intact because the flexibility of the cable between the display and the breadboard will make it easier to move the display around to where it is visible.
Is it a 2 line display? The '162' in the 'P16245B-C R3' code could signify 16x2.
Most likely it is a 16x2 for the reason you mention, but it really doesn't matter at this point. Once he gets power applied the configuration will become apparent.
Don