The Mazda Rotary Pick-Up has a 4-barrel downdraft carburetor, while the piston engines have a 2-barrel downdraft carburetor. Starting on piston engines, remove the air cleaner and duct. Then, disconnect the accelerator shaft from the throttle lever. After that, disconnect and plug both the fuel supply and return lines, then disconnect the leads from the throttle solenoid and deceleration valve. Detach the vacuum line from the throttle spring, vacuum line, and cruise control cable if applicable, and the choke cable. Remove the nuts that attach the carburetor to the intake manifold studs. Sometimes you need a small socket with an "L" shaped hex drive, or a short, thin wrench. Attach the carburetor to the manifold after new gasket installation, then tighten its nuts. Then, reconnect the throttle return spring, accelerator shaft, electrical leads, distributor vacuum line, and fuel lines. If applicable, adjust choke cable and cruise control cable, refit air cleaner and duct, and finally start the engine and check for fuel leaks. Remove the air cleaner assembly with its hoses and mounting bracket. Disconnect the choke and accelerator cables. Disconnect the fuel and vacuum lines from the carburetor. Detach the oil line from the carburetor to the metering oil pump. If applicable, disconnect the idle sensor switch wiring. And then remove the carburetor attaching nuts or bolts, gasket, or heat insulator. The installation process is the opposite of removal, and a new gasket should be used. The float bowl should be filled with gasoline to assist starting.