Tailingloop is correct. This design is very similar to the old Gunnison reels. If you are reasonably mechanically inclined it should not be any trouble.
I'm just looking a the diagram, but I'm pretty sure in my instructions. You'll need to carefully pry the "Drag Knob Cap" off (1), then unscrew the "Drag Knob Screw" (2) as much as it will go. Note - make sure to take notice of the initial position before unscrewing it; this could change the initial drag setting otherwise. I believe you should then be able to loosen the drag knob.
If that isn't enough to access the tippet material, then you may need to take off the "Drag nut" (5) and loosen the knob further if possible. If that is not enough, you would then need to loosen the "Spindle nut" (7).At that point, the whole spindle can be removed from the reel, which should be sufficient.
However, I would think that once (5) is removed, you should be able to remove the cross pin and thus the drag disk, and should not need to remove (7).
HTH.
"Engineers don't idle well."