Hey you I have a '70 GMC with a 350 in it, I reasontly put on a new head , water pump and thermastat on it but it is still over heating in the frist 10 min any idea's folks ?

You need to replace the radiator or have it rodded. Remember to use only a 50/50 mixture of antifreeze and distilled water. This will prevent mineral buildup inside the radiator. You likely have corrosion or mineral buildup preventing the radiator from cooling properly.