2005 gmc truck stereo removal

You will need to purchase 2 antenna adaptors.   Just go to your local stereo shop and tell them what you are trying to do, and they will be able to help. 

There is really only one way to get to the antenna plug in, and that would be to remove the radio from the dash.  Tilt the wheel all the way down, put shift lever in L1, grab the top of the dash board and pull it to you.  You may have to unplug a plug or two, set the dash piece aside.  Use a 7MM nut driver or ratchet and socket to remover the 3 screws from the radio. 

****** Getting switched power may be a challenge, ********maybe somebody else can help with that. 

grab your switched power from the fuse box, unscrew two bolts holding the lower dash panel, then remove it, you will then have your wiring for the fuse box accessable. your accessory wire will be orange or brown. they are going to be thicker guage wires as the smaller ones are on the other side of the fuse. put a fuse holder on it and run the wire back to the radio. make sure it doesn't rub or get pinched by anything. tape it or loom it if you choose.