[RC-Monster Mike]

Shortening the pin would not be necessary if you install the pins and outdrives into each endcap before assembly onto the diff cup(don't forget the bearings). The wavy washers are just under .5mm thick each - the picture looks like it should be a decent starting adjustment, but it will vary from vehicle to vehicle, track to track and also with different sized spur gears, so the 1.25mm is just a starting point. :)