This is very easy. Jack up the front passenger side. Put a jackstand in the correct place. If this is a small block, the fuel pump is under the alternator. There are 2 bolts holding it to the block and 2 lines, 1 going into it, 1 going out. Un hook the lines (One will be rubber, it should be replaced). Then put the new pump in, and hook it all back up in the opposite order. Its pretty straightforward.
It should be inline just before the fuel pump and located on the frame. It will have a filter with a vent line. You have one there to be proud of. The more original the higher the price for it.
Its under the Listerine plate.
look on the fuel line on the passenger side in front of the engine by the cylinder head.
When at Google type in the search bar...1985 Plymouth grand fury pictures. When at eBay type in the search bar...1985 Plymouth grand fury. try allpar.com or the mopar webring
Try a salvage yard.
Check out the related link for instructions on how to change the fuel filter in a 1999 Plymouth Voyager.
The OEM tank held 19 gallons. It will have to be an OEM type tank or it will not fit. You can buy a replacement at the link I will post.
A good muffler shop can fabricate a dual exhaust system for that car.
check the fuel line filter, usually full of dirt , or if it is fuel injected ,, the rail could be plugging up going to the injectors. or u have water in your gasoline..if not any of these see a good mechanic one who specializes in mopar..good luck..as i had a plymouth fury myself for many years and was a great car and lots of power on hiway..as well as handling, you couldnt ask for a better car..
If you remove the filler hose from the side, you can siphon out the fuel.
The fuel pump is inside the fuel tank on a Plymouth Acclaim.
It's in the gas tank, the tank has to come down to change it.