I replaced my spark plugs after the cooling ordeal. Don Wessel Honda in Springfield did not have the stock "B" series NGK spark plugs in stock, so I had to settle for Autolite Iridiums. I bought 6 so I could personally index them myself. Having never done indexing before and going off of a 10 minute research break, I'm sure that I did this wrong. But it seemed to work out for me in the end! Here is how I did it:
That simple. I marked the top and all the way down the plug with a Sharpie to indicate the location of ground electrode. I marked all 6 the same way. The only thing left to do was to install all 6 in each hole and check the location of the spark.
I got close with 2 of them
They both had this orientation. This photo shows the ground towards the exhaust ports (rear of the car) and the spark positioned towards the intake ports. In the third, none of the remaining ones were close. So I picked the best, which had the ground facing the driver's side tire, i.e. ~90* off "optimal".
The old ones definitely showed wear and white build up from running lean, which would be normal for this car. My butt-o-meter said there was a slight difference when I left the shop and went up the hill going away from work.