I own a 2003 Mazda Tribute ES 6 cylinder with 60k. I have noticed lately that my miles/gal. seems to be decreasing. I thought that I would attempt to replace the plugs myself however I don't know where they're located!! Can't even find the spark plug wires. Can I possibly be that ignorant? Are there some major engine parts that I must first remove to have access to the plugs? I figured that about $20 for a set of plugs will be all that it'll cost me. Have no idea what it'll cost me me to take to a shop. Can someone please tell me if this is a fairly easy 'do it yourself' job and if so how do I go about replacing the plugs myself? Appreciate any step-by-step guidance you can offer me.Thanks, Jim