Speed Switch / Pot Switch on BBB

Back again for another round on my buddy's 2005 or 2006 Bad Boy Buggy Classic. The dual Sevcon 633T45312 controllers are giving a 6 flash fault. The three indicated test/ failures listed in the controller set are 1) Input wire disconnected (white/ black lead), 2) Speed (Pot Box) adjustment needed, and 3) Pedal depressed at Power up.

Any idea as to what the part # is for the speed switch?