The radio in a Toyota pickup, while adequate, may not be exactly what you're looking for in a radio. Many aftermarket units exist that can replace the radio with a better amplifier and with more control over the sound quality (i.e., equalizers). You'll need a basic set of tools and 20 minutes to remove the radio.
Adjust the heating vents down.
Grab the plastic bar between the heating vents and the stereo and pull the assembly straight forward. This should remove the dash panel covering the radio.
Remove the four screws holding the radio in place and pull the radio out of the DIN slot.
Remove the 6-pin connector and the antenna plug from the back of the radio.