How Do You Add A Switch?

I would like to add rear-facing flood lights attached to my camper shell.

I already have a wire installed that runs from the back of my truck to the battery. It is a marine grade wire.

The writing on the outside of the wire says 1A AWG. I think this means it is a 10 gauge wire, but I'm not positive.

I know if the wire was thinner it is relatively easy to "T in" a switch, but I was wondering what would be the best way to add a switch to a wire this thick?

Thanks.

 

You’d need to wire that into a relay harness, which would then give you a smaller gauge trigger wire to tie into a switch. Like this:

$14 Nilight 10011W 16AWG Wiring Harness Kit-2 Leads LED Light Bar 12V On/Off 5 Pin Rocker Switch Power Relay Blade Fuse for Jeep Boat Trucks, 2 Years Warranty

https://smile.amazon.com/dp/B073TYH2VN/ref=cm_sw_r_cp_api_glt_fabc_XBFNFZRYBQWE1XN5SGY6