Here is a picture showing the timing mark that is on the drive gear on the governor shaft. It is nothing more than a simple dot.
I had a terrible time finding that little dot on the tooth when I had my governor off the tractor. Seeing the orientation of the dot directly above those two slots narrows the search considerably.
I ruined the first magneto oil seal I attempted to install during the process and the second one didn't go in unscathed. I ordered and received my seal tool from Earl and armed with this picture, should find the next oil seal installation a relative snap compared to the last two tries.