Having trouble starting my 1972 240z, just got it about 6 months ago and it had set for 8 years. Everything is original motor, transmission, differential, etc. Engine runs a little rough once it is warmed up. Drained the gas and refilled tank and included new fuel filter. New plugs, plug wires and air filter. The SU carburators round top could use some cleaning I guess, but not too experienced to do this myself. I have to turn the key to get the fuel pump working before I try to start it. Then I have to pump the gas until it finally turns over. Seems like the carburators are starving for fuel. Strong gas order like it is running to rich. I have to leave the choke fully open longer than necessary I think, before the engine will run without coughing so much. Any help is appreciated.