well it was a bitch at first for me also when i took my diff out.(w/o separating the tube)
i removed the steering linkage(tie rods and center bar). i positioned the pitman arm all the way towards the drivers side.
i also put the jackstands under the a-arms so that they didnt droop down. i needed the a-arms to sit straight to get the clearance needed to get the diff flanges in between.
also, i put tape on my oil pan to prevent scratches.
when removing you have to lower the passenger side down first, then you have to rotate the diff a little while lowering it. just remember the way you took it out and install the same way in reverse.