I pulled out plug number 1 and found that the timing marks on the pulley are dead on. So I timed it the Ron Kwas way to 15 BTDC and then checked it running with a timing light, and indeed it was firing on idle at 15 BTDC. So that is where it is running now. And having run it for a hundred miles or so, it seems to be running great. What is different is that I swapped the thermostat from a 190 to a 180, so it runs cooler. And I cleaned the plugs. Number 1 looked like a souvenir from the Titanic. Lots of crust. the other plugs were less crusted but still holding plenty of debris on the electrode. That's after about six months, or 5000 miles. Lots of oil has been burned in those cylinders in that time. Six months ago I also did a compression test and the results were: Dry, 160,156,158,168; wet,170,170,170,180. I think I will do the head part of the engine...with those numbers would you recommend doing the rings as well?