This guide from 1984 covers the VIC 1541 disk drive. It is also applicable in most cases to the 1541 drive for the Commodore. The VIC 1541 was the first generation of the 1541. Commodore selected certain discrete components which were in the VIC 1541 and combined them into custom IC’s and utilized them in what they called the 1541. Functionally there is very little difference between the two drives but Commodore renamed the schematic reference designations.