The fuel shut off solenoid/linkage may be binding, the plunger maybe sticking and or the the fuel shut off solenoid relay (on firewall above fuel filter housing may be malfunctioning). Usually the relay will cause a no start, intermittant start issue, rather than a no shut off complaint. Also, do not concern yourself that the smaller of the two relays has no harness plugged in to it. This is normal on 94-96 trucks the fuel heater uses the "empty relay" I think that model year may also have the "ASD" relay in the power distribution box. You might try another 30 amp relay to swap out to see if this helps. It may also be wiring issues and maybe a bad ign switch.
The shutoff solenoid moves a lever on the side near the bottom back of the pump pump up and down. When the ign switch goes to the start position, then is released to the run position, the plunger in the solenoid pulls the lever up (via the pull coil) and allows the fuel to travel thru the pump. Once the solenoid is retracted (pulled up) another coil acts as a hold coil (less amperage) until the power is removed (key turned to off position).
When the ign switch is switched to off, power on the "hold" coil is released and the spring tensioned plunger forces the lever down, shutting down the fuel supply.
Next time it doesn't shut off, jump out and see if the solenoid is still retracted or pushed down.
Goosing the throttle may have nothing to do with it other than to "shake" it loose and let the plunger fall down.
I think there are photos and further discussions on
www.dodgeram.org site.
Good luck,
Andy