I have a pair of WECO (Made in Germany) pedals that I would like to disassemble and service. Has anyone ever done that? On the Lyotard pedals I have done in the past, the dust caps either pry off, or screw off easily. Here ... not so much. Are these sealed and I am just out of luck, or is there a trick? I wouldn't think that the Germans, of all people, would make something disposable ...