The vacuum pump rebiuld is a DITer, I can't remember all the detail steps, you will need to remove the pump, change out the diaphragm. You will need to clear out the check valves, they are behind the small plate in front. Be careful, it is spring loaded behind the plate. These two valves must be installed back the same way, you will know if they are wrong when you can't shut off your engine.

No special tools required.

jack