You should raise and support the vehicle, place a drain pan under the transmission oil pan, remove the oil pan drain plug, and the bolts and position aside the range selector cable bracket for clearance while lowering the pan and the oil pan bolts from the front and sides of the pan only, loosen the rear oil pan bolts approximately 4 turns, lightly tap the oil pan with a rubber mallet, remove the remaining oil pan bolts, the oil pan and the gasket, the filter, and the filter seal, discard the seal, inspect the fluid color and the filter, pry the metal crimping away from the top of the filter and pull apart, clean the transmission case and the oil pan gasket surfaces with solvent, and air dry and remove all traces of the old gasket material.