I have been following the tutorial and admit to wondering if I can do this. But I have also looked closely at my 15-91 and besides being full of oily cobwebs and oily dust in every crack and crevice, I found a section of the wiring to the foot pedal has some cracks with the insulation fall off. I'm not too worried about that because it needs a new foot pedal anyway so I can buy that whole thing on that great website that SherriB gave a link for. But I also saw on that link the kind of gunked up grease that is likely to be inside of the machine and needs to be removed... and fresh put in. Why did I think that just because it looked pretty and had parts that moved easily that it should be "good to go?" And speaking of gunked up grease, a tube of partially used Singer motor lubricant is in one of the drawers. Is it likely that this tube is still okay to use?