The Singer 101 was the precursor to the 201 and uses Class 66 bobbins. The bed on my 101-3 is held by 4 screws and is a bear to remove at times. Another difference between some of the 101 models is the spider wick system. On mine (1928) has a shallow well where you add oil. If you overfill it you cannot lower the head into the cabinet without spilling oil everywhere. There are covers on the bottom of the head that pop off to clean and re-grease the gears. To remove the motor you have to give the motor cover a twist to remove then unscrew a small screw on the front of the pillar to remove the motor after removing the handwheel. After that things are fairly easy and simple to do. I clean and re-grease yearly. Phill