when you replace transmission gears - in my case, the dogs on 2nd gear are worn so I will replacing 2nd and 3rd on the input shaft (the 2 that are worn) - my question is do you need to replace the matching pair on the output shaft? can you mix and match those gears - my opinion is no - but I'm just curious.
If the gears on the output shaft are in good shape, you don't need to replace them. I had repaired an old CR125 I had years ago in this manner with zero problems (other than the fact the transmission was too weak for the upgraded suspension).