I am working on a little project where I want to put some Cree P4 XR-E 7090 (WD) LEDs into a vehicle. They draw 3.7V @1A so I know that I can wire them in a series of 4 and be ok, but what if I just want to drop the voltage down to 3.7 and run at least 4 through some sort of DC step-down? I would like to know what you guys would run for a cheap solution and what you would do for a mid-level and high-end solutions as well. Aslo a place to buy the components would be helpful.