To disconnect and remove the clutch master cylinder, begin by disconnecting the negative cable from the battery. Then, disconnect the hydraulic line at the clutch master cylinder, using a flare-nut wrench if available to prevent rounding off the fitting. Take precautions with rags as some fluid may be lost during the disconnection. Under the dashboard, disconnect the pushrod from the top of the clutch pedal, which is held in place with a clevis pin. Moving to the underside of the dash, remove the nuts securing the master cylinder to the firewall, ensuring not to spill any fluid during the removal. For installation, position the master cylinder on the firewall and install the mounting nuts finger-tight. Connect the hydraulic line to the master cylinder, adjusting the cylinder position as needed to properly thread the fitting into the bore, ensuring it is not cross-threaded. Tighten the mounting nut(s) and the hydraulic line fitting securely. Connect the pushrod to the clutch pedal. Fill the clutch master cylinder reservoir with brake fluid that conforms to DOT specifications and proceed to bleed the clutch system. Finally, check the clutch pedal height and free play, making adjustments if necessary.