If when you assembled the transmission you didn't notice any gear tooth wear, then you are likely suffering from a lack of spring pressure on the shifter fork rack locating ball. You are right in thinking that the Chief adjustment is up top. To make adjustments on the Scout, you have to get down to the bottom of the tranny case up front between the engine plates. It's simply a matter of slackening off the lock nut and turning the screw clockwise to increase pressure. Be careful not to crank it too tight. You'll know if you did if the tranny shifts on the "stiff" side. The only bummer here is you need a right angle screw driver as there isn't a whole lot of room to work with.......... Good Luck!