[mnez]

My Wevo is perfect. Installing just the shifter doesn't change anything to do with the shifting inside the transmission itself, other than a small increase in effort if the length of the shift handle is shorter than before. If it isn't right, the coupler needs adjustment, and therefore needed adjustment anyway. Follow his adjustment instructions exactly, and you will be very close. Fine tuning takes some time and iterations. Small adjustments make a big difference.
Don't forget about the cup bushing and the rod bushing.
I shimmed my springs to increase the effort - it is to personal taste, that's why different springs are available.