So let's say I build an i7 rig. What is the possibility I can uninstall the drivers off my current OS image, pop that drive on the i7 board, and have it boot into Windows successfully so I can reinstall the drivers?
I'm going with close to zero. I think you'll have an easier task, and take less time, to just fresh format. Why do you care so much to keep your current OS install? It doesn't take all that long. Download your essential programs and drivers before reformat, put them on a USB drive, pull your userdata folders, put them on an external drive or server, do the reformat, put it all back together. Once userdata is in, it will feel almost exactly like the previous OS.