Originally Posted by CosmoKramer

No you don't have to completely remove the forks. I, along with the HD service manual, describes changing the fork oil by utilizing the drain screw. Just becareful with that drain screw because it is a phillips head screw....they are known for stripping the head. Make sure you put good pressure againest the screwdriver, driving it into the screw, as you try to back it out.

Depending on your handlebars you may have to remove them. Might be a good idea anyways as it gives you a clear path above the fork caps. I think I have a bunch of pictures and a write-up I did for a friend on how to remove the fork caps. That gets you most of the way there. If I find it I'll post it here.