Blower motor and resistor

You should first figure out which one you need if those are even bad causing the problem. Do you have a multimeter to do some testing?

Sound's like you could have a bad motor or a loose connection at the motor.I wouldn't replace the resistor if you beat on the motor and it start's working on all the speed's.I would first make sure the terminal's to the blower motor were tight before replacing the motor. Here are the instruction's on how to replace the motor.
Blower Motor and Blower Motor Wheel Assembly

Removal and Installation

1. Disconnect the battery ground cable(s).
2. Remove the air cleaner in front of the blower motor (18527).
3. Disconnect the wire harness connector from blower motor by pushing down on the connector tabs and pulling the connector off the blower motor.

4. Disconnect the blower motor housing tube (19A786) at the blower motor.
5. Remove three screws attaching the blower motor to the A/C blower housing (19930).
6. Holding blower motor housing tube aside, pull the blower motor from the heater plenum chamber case (1 8A484) and remove it from the vehicle.
7. Remove the blower wheel hub pushnut and, if applicable, the clamp from the shaft. Then, pull the blower motor wheel (18504) from the shaft.

For installation, follow removal steps in reverse order. Check system for proper operation.

NOTE: When the battery has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module (PCM) (12A650) relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy.

I don't have any more detail's on replacing the motor it doesn't say anything about removing the glove box. There should be screw's or plastic push expanding pin's holding those panel's on.