You can dig the gunk out of the inside using a long thin screwdriver. Soak in solvent until things soften up. If you can find one a small diameter bottle brush works well on the inside. 0000 steel wool will work well to clean the outside. Finish up with spray brake cleaner (doesn't leave residue behind), blow dry, lube up with assembly lube and put-er together.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.