Well I installed the diff cover today. The Mobil 1 fluid that had been in there for about 30K miles (6K towing 13K trailer) smelled a slight bit burned. Not as bad as the OEM fluid that had been in there before the Mobile 1. The install went smoothly with no hiccups. The diff cover actually sits about 1/8" above the bottom of the diff itself. The back edge of the flat spot on the bottom of the diff is radiused and the Banks cover meets perfectly where the radius ends. The Amsoil pouches are the bomb for filling the diff. Cut off the tip of the spout and you can curve the top of the pouch 180 degrees to get the nozzle in the fill hole before tipping the pouch up. the gear oil flows smoothly into the diff collapsing the pouch as it empties. No need to even squeeze the pouch.