Check your oil pressure switch -- it is an interlock that will keep engine from starting if oil pressure is under 10 psi. If it has failed, you will not be able to start the engine. It is located aft of and below the fuel pump.

There are two tabs to insert wire connectors; one is connected to the fuel pump, the other is connected to 12 volts. You should measure 12 volts on the fuel pump wire while the engine is being cranked.