I've talked with Mr.Gadget a lot in the help channel about this, but i decided to create this to avoid filling up the help channel.
I have a script that has a Vector3 syncvar that throws a size mismatch error. I tested it with a float and a bool on the same gameobject and am getting a size mismatch error as well. I was able to confirm i can sync C>S on a different simpler player object. I'm not sure what could cause this.
Script: https://pastie.io/swfyyg.cs