Voltages interchangeable
For the most part, 12V & 14V are interchangeable numbers. The components are rated as 12V, the 14V number is generally a charging voltage (13.8V) most often. I wouldn't get too wound up on the voltage numbers. As the previous poster noted, current ratings on wires, switches, and fuses/breakers are much more important. The rule of thumb I use for fuse/breaker ratings is 150% of the device the fuse/breaker protects. Also, remember - fuses/breakers really only protect the wire, not the component!