Removing the oil filter plate from a small block (pics added for EL5demon340)
most mopars I have seen have the thin hex on the outside, cuz the square on the inside is a restriction-usually seen on fords-a trick I have found on anything tight is try tightening it a little first, then go counterclockwise. spray the thing clean of oil with brake clean, clean the socket, tap the adapter in with a hammer if there is room