adding a fan to a 2000 XC300

[Adam500]

My friend gave me a brand new trail tech universal fan kit.
I'd like to throw it on my 2000 XC300 gasser. My original stator recently crapped out and I replaced with one out of a 2010 KTM 300 XCW. Works great. Big fat spark and bright headlight. Is the lighting output AC like the original stator? I assume so.
The fan runs on 12V DC and comes with its own voltage reg. What would I have to do to make the fan kit work? Add a battery at least?
I've read the thread about floating the ground. Not an expert with electrical so the theory of it is a bit over my head.
Can someone dumb it down for me?