[oldmarine]

From the 2005 Dakota FSM (I'm assuming it's the same for yours):

The EVAP canister is mounted to the top of the fuel tank. Both the EVAP canister and NVLD pump can be removed without removing the fuel tank.

1. Raise and support vehicle.
2. Remove left-rear tire.
3. Remove plastic shield in front of left-rear tire. Access to both the EVAP canister and NVLD pump can be achieved from the area in front of the removed tire and plastic shield.
4. Remove vapor hose from NVLD pump.
5. Remove vapor line from EVAP canister by pressing on both tabs simultaneously.

 

[oldmarine]

The NVLD (natural vacuum leak detection) pump is the circular shaped item on the foreground of the canister in that picture. According to the FSM, after removing the electrical connector and hoses, it is dismounted from the canister by depressing a lock tab on the collar and rotating the valve about 70°

In the picture of the fuel tank, I'm pretty sure the circled item is the fuel pump module. It contains the fuel pump, fuel pressure regulator, and fuel sending unit. It's reportedly a bear to get the lock ring loose and removed, so if you're not having any issues with fuel delivery and pressure or fuel quantity, I don't recommend removing this.