From the KJ FSM...
"The 186FIA (Model 30) axle..."
Not sure if the diff cover is the same as the TJ/XJ D30. the TJ/XJ D30 is a 181 FBI axle. The FIA I presume means front independent aluminium, as FBI means front beam iron. The numbers I think are ring gear diameter in mm, so the KJ D30 may well need a larger cover.
Just had a google. It apparently can't have a heavy duty cover fitted as the suspension mounts to the front and has a skid that protects the diff anyway.