To replace that right side crank seal, you do not need to split the cases. You simply pull the right side cover, remove the clutch etc to gain access to the seal, pull it out (a wood screw and pliers used carefully works), then drive in the new seal, being careful not to damage it (large socket, seal driver, or an appropriately sized piece of ABS plumbing pipe works). The reassemble and test ride.
Also, there was no 1995 CR 80 Expert. It was intro'd in 1996. It could have been converted, or the year is off.