Just seems that if you were some sort of electrical engineer that could actually do the wiring yourself you'd know exactly where to look and it wouldn't be on a car forum.
Do yourself a favor and just buy one that's already made for you, you'd be surprised with what's really involved with making one of those.
let me dig up where I bought my kit. it was 50 dollars and with good instructions, theyve worked, it was easy and professionally clean. if youre not nervous about cutting and cremping wires then youre ok. I think I got it off of eBay, I'll get back to you.