you shouldn't need to remove any trim to do it. it should slide straight out once you push the locking tabs out towards the sides of the truck. then reach in and remove the metal cage that holds the radio it also has tabs that may stop it from being pulled straight out.
if you wanted to remove the trim pieces the dash pad (the one that goes around the radio) is held on by 6-7 bolts i think they are 8 mm. you need to remove the glove box and then reach through the opening, you will need to remove the radio to get them all. the horizontal trim piece between the dash pad and glove box will pop out if you pry it out i think there are 5 clips, be careful they can break easily. if you want to go further and remove the trim around the hvac controls there are 2 small bolts on the top and 2 clips on the bottom