Got your PM. A 1-tooth error is an error of 20*, as explained; it's timing at the crank that signifies. The OEM cam timing is specified for the very start of the valve opening at an inspection valve lash of .012". If you want a quick-and-dirty way to tell if you're in the ballpark, without degree wheel or dial indicator, here's what to do.
With the motor at TDC and left cylinder valves closed, remove the left cylinder intake valve cover (easier to turn the crank from that side), then set the valve to the inspection lash of .012", and insert a piece of cellophane between valve stem and tappet. Rotate the engine CCW until the valve closes. Pulling gently on the cellophane, continue rotating CCW just to the point that the cellophane is released. This should occur at 36* BTDC--very close to the full-advance timing mark.