i have a MAC cold air filter and it looks like it hasnt been cleaned in 70,000 miles. so i was just going to get the k&n recharge kit but none of the local stores had one. what else is safe to use to clean this filter? i've heard about using a lot of things to clean it from some people but then other people told me not to use the exact same things. looked online but came up with nothing. whats the best way to clean this thing?