Many Thanks Roids, I never used the dial indicator. I put in the bolt, marked the 12:00 position on the face with a dark black or blue marker after it was set against the piston once the pulley was backed off of the timing mark. My 81 seems to like the performance setting recommend in the Bentley, just a tad better than a full 360. It gets it pretty close and I fine tune it with the engine running and listen. If you wanted it to be less than 1mm say .88 then you would be looking at .88 * 360 = 317 degrees. Each edge of the bolt is 1/6 of the total or 60 degrees. So it would be five and a bit about a third positions from the high noon mark.
