Just wanted to see if anyone could answer this Since didn't get a response from MIP. I was looking into ordering the kit and some spare bones for the 13.5 system. I came across conflicting info on their website. When you buy the kit, it says the rear bones are 67mm long, but if you just want replacement bones, it says they are 65mm long. Does anyone have the correct measurement so I know I'm ordering the right parts? Thanks!