If it were me I would completely disassemble and go for it.
Might want to tape off the ends of the axle tubes and stuff a towel or something in the center. Just make sure to flush out the housing a few times when your done and get it good and dry. Another way would be to leave it all together, sandblast and then take it all apart. 6 one way, half dozen the other. Just don't aim the blaster right inside, you just want the outside blasted.