Fuel Pump relay 1972 280SE 4.5

My 72 280SE 4.5 has been dying and finnaly quit for good tonight. It had not been ran for 2 years until last Friday. Since then, it has been running "rough" and has been "sputtering" and dying at stoplights. Tonight, when it quit, it could not be re-started. The engine just cranked and never "caught" when ignition was turned. There is spark to the coil; to the distributor (fuel injected); and to both front and rear fuel pumps. Fuses checked and all are good. No fuel appears to be getting to the engine (?). Is this a relay problem? If so, how are they repaired/replaced? I dont have a shop manual (yet!). Any help would be greatly appreciated!