Now would be a good time to re-grease the steering head bearings, since it is not much more work. The instructions in the Clymers and Haynes are for removing the forks. The owner needs to modify the instructions to allow removal of the lower legs to replace the seals and not the entire fork assembly. The springs for the forks need to be released - which means the handlebars and fork plugs need removal. Once the fork spring is uncompressed, the bottom yoke pitch bolts are loosed to help in removing the lower fork. Remove the lower fork, replace the seals, then reassemble. Good luck!
edit: here is a thread talking about replacing gaiters on a R90/6 and adding fork seals.
http://www.bmwmoa.org/forum/showthre...ferrerid=51262
If your R80RT does not have gaiters, that may be the reason you are replacing the fork seals.
Also, the springs to not need to be uncompressed to remove the lower sliders. Following the link description or that from lostboy will work. The Clymer and Haynes (and my) descriptions require unnecessary steps.