rear main seal

The 83 XE 250 had the dog turd type rear main seal,
Loosen off the engine mounts, pull the through bolt and lift the engine, refit through bolts into engine mounts above the chassis mount and lower engine onto bolts on top of chassis mounts.
Drop/remove the sway bar.
Drop the sump after draining the oil and drop the rear main cap. The lower seal can be easily replaced and if you look up the upper half can be seen and replaced.
Shoot of a job, being dripped on but quickest with the engine in.
Removing the transmission does not help in this situation.
Hope this helps.