Best to tap the positive source (red wire) off one of the two bolts on the under hood fuse/relay for the positive and use a chassis ground as close to the lights as possible for the negative negative(black wire).
To do what you are requesting you must have both an inline fuse rated to the lights and a Bosch style relay along with a three connection toggle switch. PLEASE do the math and use the right fuse for your lights and make sure you have metal to metal contact on your chassis ground. I encapsulate all chassis grounds with a little RTV or the like. I also highly suggest you solder your connections. However if you do use but splices dose them with dielectric grease and wrap them in bulldog tape and a layer of electrical tape. You will thank me later when they never fail.
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I recently installed mine and they work great if you follow this schematic and install the right fuse.
Also, please remember you MUST disconnect the positive from the battery and wait ten minutes before you do ANY electrical work on Christler systems (pun intended) as they are notorious for bad things happening if you are working on them live.
As I am waiting on the rest of my lights and such, temporarily I used this very affordable plug an play harness. One for my ditch lights and one for my rear work floods. (Disclaimer, I bought mine locally from Menards for 17.99USD)
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