I just got the car with 125,000 miles on it (some of you might know from my previous post). Runs great, but I have no clue when the last time the plugs were done, so I might as well change them. What kind of plugs do you guys recommend? Im concerned with complete smoothness, if that helps. Also, should I leave them gapped at the setting at which I buy them, or go with a different gap (I have a muscle car too, so Im always changing the gap to get the most performance; not sure about caddies - if I should just leave the gap at whatever they come with)? Last of all, should I do spark plug wires as well, or leave mine in (and if so, wich should I go with)? Thanks again guys! By the way, how difficult is it to do the plugs on this 4.9? On my ls1 trans am its a complete bitch; Im hoping this is easier!