What is the correct fill level for the front and rear axles. Is it to the bottom of the fill plug? Service manual states 1/2" below fill plug on Dana 60 and 3/4" below fill plug for Dana 80. I thought I remember while reading about the MagHytec differential covers something about the fill hole on the factory Dana 80's not located properly and the proper fill level was to the bottom of the fill plug and not 3/4" below. Is this correct or am I incorrect?