Does a 1988 Chevy C10 with EFI have an oil pressure switch that shuts off the fuel pump if is low?

No, a 1988 Chevy C10 with EFI does not have an oil pressure switch that directly shuts off the fuel pump if the oil pressure is low. While low oil pressure is a serious issue, the fuel pump's operation is not directly tied to it in this system. The fuel pump is controlled by its own circuitry and relay. The engine's computer might detect other issues stemming from low oil pressure and alter fuel delivery or even shut the engine down as a safety measure (via other sensors), but it won't directly cut the fuel pump via an oil pressure switch.