Hi, I would like to replace the oiling felt in the bobbin area of my model 66 machines. I can't find any info on this subject. An internet "search" shows warnings to not remove it but I can't find any info on how to replace it. Does anyone know where to purchase replacement felt and how to replace it? I have tried to disassemble the machine but was never able to remove the part that has the wire coil for holding the felt. Thanks in advance for your help!