Hi, I've been Foraging underneath my rover and I decided to check the universal joints and greese them. I noticed i couldnt pull back the plastic guard on one outside axle to check, it cant go over this square metal thin block, not like the other side. My question is, are these metal things factory or have they been added later for balancing or has the universal joints been installed incorectly so that one side is back to front. The black arrows shows what i mean. The green is for the correct installment?