blower fan switch dosnt work

i have a 1993 grand am gt coupe with a 3.3 v6 the blower fan switch dosnt turn on high but the other 3 settings work just fine... also i heard that if the oil sending unit goes bad then the fuel pump wont work.... well my oil sendin unit i think is bad and just today the fuel pump stopped working... i want to know the dificulty of changing it if its in the tank or inline.. thanx

The fan speed is likely the blower resistor. Its mounted on the firewall about middle of the engine compartment halfway down the engine compartment. Normally a failed resistor though will stop working on the 3 low speeds and bypass the resistor for high speed so if you have a failure you can still blow the windows on high. Check the dash switch first. As far as the pump, you need to drop the tank.