A quick back ground on what I am doing. A personal friend of 30 years was diagnosed with cancer. He just retired last october. His retirement project was a 52 F1 1/2 ton. With my wifes blessings I decided to finish the truck for him. the project is going well but I am at a snag. The engine is a 88 FI 302. Another friend has built the motor free of charge. It was converted to mechanical fuel pump. The fuel pump inlet and outlet are 5/16 and the new gas tank is 3/8 line. Will be running an Eldebrock 600 which has 3/8 inlet. This engine has a 2 piece eccentric on the cam. Does anyone know if this pump will run the engine if i reduce the line sizes to 5/16 or is there a pump that has 3/8 inlet and outlet for that will fit this block. Any help would be greatly appreciated.