Fuel pressure regulator?

4.3L V6

If its the CPI spider system its under the upper plenum on the passenger side-TBI behind the injector

Looking at the pic the pressure regulator its on the L/side and R/side Nut kit

Properly relieve the fuel system pressure and disconnect the negative battery cable.
Remove the fuel return pipe from the regulator and discard the old O-ring.
Disconnect the vacuum hose from the regulator.
Remove the fuel return pipe clamp.
Remove the pressure regulator attaching screw, then remove the regulator and discard the O-ring.

To install:

If the old pressure regulator is being installed, check the filter screen (if equipped) for contamination and replace, if necessary.
Lubricate the new O-rings with clean engine oil, then install them on the pressure regulator and fuel pipe.
Install the pressure regulator onto the manifold.
Make sure the regulator attaching screw threads are covered with Loctite 262 or an equivalent threadlocking compound, then install and tighten the screws to 31 inch lbs. (3.5 Nm).
Connect the vacuum hose to the regulator.
Make sure the new O-ring is in position, then connect the fuel return pipe to the pressure regulator and tighten to 22 ft. Lbs. (30 Nm).
Install the fuel return pipe clamp and attaching nut to the lower intake manifold assembly.
Connect the negative battery cable, then pressurize the fuel system by cycling the ignition (without attempting to start the engine) and check for leaks.

93 CPi's had other problems beside the regulators. The fuel lines in the intake have been known to pinhole, causing raw fuel to be sprayed into the intake plenum. The lines are on the d/s, so I would suspect that could be the problem. Remove upper plenum, and turn key on, but DO NOT CRANK, if any fuel leaks they will be readily visible

Make sure no pressure on system, Remove top torque screws, the autostore sells a fitting to remove those. You should be able to remove only the top part. Picture below.

You shouldn't have any problems, just put it back together the way it came off. I don't use a torque wrench on screws that small, maybe I should? Torque specs are below.

You bet.

It looks like this below and its located on the fuel rail