Switch Replacement Amperage

[Vanhandler]

I have a nilight lightbar which I have wired to my starter battery. The rocker switch that it came with is a 12v 20amp switch but that switch does not fit in the dash- and I don't want to custom install it. I found a switch that fits perfectly in the blank spaces but it is a 12v 16amp switch. My question is how do I determine if the 16amp switch is sufficient for the application?

 

[400bird]

By measuring the current draw if the relay.
But, it's a relay. If wired correctly, most relay coils draw less than an amp to close. All the current for the light should go through the relay.

If it was really 783 watts that would blow out most standard relays.
783 watts/12 volts = 65 amps
Even with the engine running and alternator going, it's a lot of juice.
783 watts/14 volts = 56 amps