I found an 87 XJ which i thought might have a D44 in it.It had a metal drain plug.But on the top left it said 35C.I thought all 87's had a D44.Guess not huh?
Bingo, give that man a prize! Is there a prize for knowing your butt plugs?
You'll also notice the metal plugs are lower on the cover. The non-clip wheel bearings are pre-greased versus using a gear oil bath on the c-clip variety, so the fill level is higher up towards the middle of the axle tubes. This also means that you can't swap on an older cover to get the metal plug, unless you prefer you wheel bearings dry.