I have a 68 with what I thought was a 302. The vin says its a 289. The motor has been rebuilt be the po. Car sat since 1998 and was never started. I finished hooking everything up on it to get it running. It originally had a radiator and water pump that was on pass. side. The radiator was junk and the po bought a new one but it was a driver side so I switched the water pump to match the new radiator. It was missing the brackets so I got a serpentine pulley set from Summit. The stock crank pulley was a 3 groove 4 bolt. I relocated the timing pointer to the driver side. Verified TDC with a piston stop and used degree tape to set timing. I also switched out the 2bl for a 4bl Holley. Started engine ran fine in driveway drove down road and she gets hot to the point was she is spitting coolant and steam out overflow. I have burped system even jacked front of car up. It has a 3 core aluminium radiator, flex fan, shroud and an electric fan to push air thru. New bottom hose with spring and thermostat. I removed heads had them checked and they were warped so had them reworked. Head gaskets are on right. The only thing that I can think of that might be wrong is the pulleys are the wrong diameter but I sold the old ones so I cannot verify there size. Does any one have any other ideas? I also by passed the heater core because it was leaking.