Bissell 1672 BIGgreen Wet/Dry Vacuum "instructions air clock" Questions

...instructions for opening up the motor unit. Don't pry up on the very top disk, which is an air outlet. It will only break off and won't allow access to anything. If you do break it off, drill holes ...

instructions on opening up the power unit so I can clean out dog hair? Thanks I have the Bissell Big Green model 1672 and have used it for many years. Recently, the fan or suction blower began to emit