Shift drum

[djohns]

Ready to button up my gear box on the 1964 CA77 and I look at the diagram to make sure everything is facing the right direction. Counting teeth on the gears with the cotters attached and I find that they are both 23 teeth instead of 23 and 24 teeth for part #'s 23430-262-000 and 23461-262-000 respectfully. Looks like one set of the cotters was changed at one time as it has an offset in the tabs vs. flat like the new ones I bought. A change made in the past for lack of proper part by STM (shade tree mechanic)? What effect will this have on the shaft output speeds besides the obvious. I have a 1965 set aside for breakup that I could get a gear from if necessary. Also my shift drum has only three "pins" on the end for the gearshift arm to push/pull. My 1965 has four pins on the end. Why the differance? Are the shift patterns different like one down/three up and the other closed circle one/two/three/four/neutral? Thanks in advance.