I've tried both. I set the initial with the body clamp and then screwed it up worse with the octane adjustment. The screw on the body clamp has its head to the rear, so it is a bother. I ought to reverse it.
I did drive in to town today, but it took forever to get up to 50. I stopped and changed the timing and idle any number of times. I felt lucky to get home.
At idle should I expect the spark advance to be in its most extreme retarded position?
I'll be reading the answer in the morning, just now it is late here.