i Thought about doing that also and ive heard from many many people that thats junk. Stock air box with Slp cold air intake is the way to go. With the boots from the carb, it just sucks in all hot air and you loose performance.
yeah you need that sensor. just plug it back in and zip tie it somewhere near the carbs. that is the temp sensor for the DPM. i just zip ties mine to the center of the carbs inbetween the 2 K&N's but i plan on making some type of bracket.