Fuel and ignition revamping (solved?)

Ok, I believe I have this one licked! As I sat and listened to the car in drive at idle with fans on it just seemed as it was intermittently dropping a hole. Had the wife hold the brake as I just watched and listened.... low and behold I heard a tick then saw an arc! Bingo! Thinking I may need to fatten it up at cruise a smidge, that may drop the cylinder temps a little? Thoughts?