Take off the headlamp assembly and the plastic inner fender on the passenger side of the Neon. There are several screws and fasteners you’ll need to undo with a screwdriver to get to the windshield washer reservoir. Remove the filter neck and three mounting bolts using a 10mm socket wrench.
Undo all the leads to the reservoir, including the washer hose and three fasteners. Rather than simply lifting the windshield washer reservoir out of your Plymouth Neon, you need to remove it through the fender opening. If the pump lifts out with it, twist it off and pull it away from the reservoir.
Reassemble the unit by attaching the washer pump to the new windshield washer reservoir, installing the new seals and putting the reservoir in your car by screwing it into place, replacing the three fasteners and attaching the washer hoses.