My 2004 F350 has 151K miles. U-joints went out and changed them on the front axle. I'm trying to change my dust seals. I have the outer seal on the knuckle, easy to take off and change. Inner seal by gear housing; hard to take off or don't know how to. The one on the axle housing end ( by the u-joints) don't know what its called or part #. can someone help?