As far as I know, all the damper rods have that aluminum "cup" on the bottom, but if your forks are really gunked up inside, that part may have remained stuck in the bottom of the lower. If they are really gunked up inside, just rinsing them out with solvent ain't gonna cut it, you'll need to get in there and physically swab them out .....
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Get some 1/4" steel rod, bend a small eye in one end so you can thread a rag into it, dip it in solvent and swab away. You can clean all the crud out and get the insides of the lower clean as a whistle.