Well, let’s first start with why do you think the shift rod needs adjusting? Give us a little history on what is going on with the engine and what service work has been done to it lately…
The two screws, #43 and #44, must be loosened, not removed to adjust the lever for equal travel in both forward and reverse. If you get carried away and remove the shift lever, note the star lock washer #57, goes between the shift lever and the shift shaft, #39, and not under the square nut, #38.