speed control cam plate mark...
 

OK, I've been playing around. I've did the adjustment to the speed control lever (tightening) per the service manual (2-43). It's good and tight now. Maybe that had some to do with the lever "falling" into reverse. I haven't got that far yet... Afterward I got noticing on the speed control cam plate, it has an arrow. What is this arrow for? I've got the tractor in "neutral" in this pic and you can see the relation of the arrow...