Still, it wouldn't hurt to eyeball the relative height of the f/r fill plugs. The front should be noticeably lower than the rear (I'm betting that's what Vinman meant to say). If they had been inadvertantly swapped front and rear, the higher plug in the front could contact the locker. And just as bad or worse, the lower plug in the rear could eventually starve the axle bearings of lube.
Good point. I'll check to make sure cover has the lower filler plug.