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1968-1982 Vacuum Hose T connects at the firewall. This Hose T attaches the large vacuum source hose from check valve to reservoir hose and heater control vacuum hose.
It is located left of the brake master cylinder, outer firewall.
Approximate Hose Diameter Measurements: 1/4" x 1/4" x 1/8"
See tab marked Parts You Will Need for vacuum hoses, routing diagrams and check valves for your complete C3 Corvette vacuum system.