The internal rod has a thread on the end that goes into the "cap" bolt, there is also a nut on that rod to lock it against the cap bolt. How I got mine apart was to remove the fork from the triple tree, once the cap bolt is loose, slide the chrome fork leg down into the aluminum lower and then the rod & lock nut are visible for work. Strange design & not fun to service, mine fell apart or the PO didn't reassemble correctly, so I had to strip it all down & figure it out
Photolar's method will also work, probably easier than mine, wish I had known