Andy, I'll give you my very best shot.
You will never cobble up an operating system yourself without a considerable amount of studying on the subject. Been there, done that.
If you want to do it yourself, buy and read these three books by Carroll Smith. This guy is the guru in my opinion, having been the crew chief for Ford Motor Company when they went to LeMan and beat the Ferraris. I couldn't make heads or tales of suspension and steering until I absorbed his writings.
http://www.amazon.com/Prepare-Win-Ca...0975296&sr=1-6
http://www.amazon.com/Engineer-Motor...0975296&sr=1-3
http://www.amazon.com/Tune-Win-scien...0975296&sr=1-1
There is nothing wrong with buying used books to save a few sheckels either, I do it all the time.

Like I said, if you want to do it yourself, absorb Smith. If you want to install something that will work the first time and don't want to learn how to do it, then take falconvan's advice and purchase a kit that has been engineered to work properly from the git-go. The chances of you cobbling up a system that will work properly without the knowledge gained from an expert is probably somewhere in the 10,000 to 1 range.