[SantaFe66]

You will need to pull the axles out a bit to clear the third member. Drain the lube with a suction device (should be about a gallon). Get a jack under the third member unless you're a bench presser, unbolt it (after unbolting the yoke from the driveline & slide the driveline forward or pull it out of the tranny), then move the third member forward off the bolts. Clean the surfaces, silicone both, put the new gasket on, slide it back in, rebolt it, pop the axles back in, refill it with lube and you're good. Not complicated and you don't have to disassemble the ring and pinion, so no adjustment issues.