Ok so I do have a speed cal, its a brothers performance one though. I called them and they are supposed to send me the instructions via pdf in an email but the guy on the phone didnt give me too much confidence. Are the instructions in the link you gave me the same or is it a different pin configuration?
I haven't seen the brothers performance speed cal so I can't say if it's the same or not. Hopefully you'll get the instructions from them soon and get your Mach's speedometer reading right.