I run a K&N on my 6.0. With a custom plastic pipe intake. I hate K&N's but when they have a million different sizes its hard not to use one. I would rather have an AEM dry one, that doesnt need oil. Either way I am not a believer in the theory intakes and mufflers add tons of horsepower, so get one that works and youll be fine. Hell the stock Donaldson filter on my Dmax will outflow anyone elses and its the stock OEM filter for them. :****:
If you want a relatively small round K&N that will slip perfectly on your MAF, I can get you the part number off of mine. I think it was less than 50 bucks from Summit