I looked up the plenum gasket. My truck doesn't really have those symptoms. It has the symptoms of the crankshaft position sensor and temp sensors, and EGR valve. Also when they were putting the fuel tank back in they broke the rollover valve and didn't tell me until after they were done putting the tank in. So i'm sure that plays a role in the truck running right. How do I go about testing the MAP and EGR. By checking the plug harness and what else. I really need this truck running.

 

Bummer, you have to take the pump out but there is a fix. The OE valve is no longer available (NLA)
IDk if having that line open or closed off would affect how the truck runs.
https://dodgeforum.com/forum/1st-gen...fuel-pump.html
Found this https://troubleshootmyvehicle.com/ch...e-map-sensor-3
Scroll down it has links to other issues you have mentioned.