i was wondering, how can you tell if you have the chinook 3 or the 2... i was UNDER THE IMPRESSION that i got the chinook 3 from NGK yesterday but when i look at the 2, i dont know how to tell the difference... is there any difference and is the quality lessened in wither of the 2, or even 3... are all of them equally reliable??? just some clarification would be nice. thanks guys