Upper control arm removal.. HELP!!!

Make sure that in addition to the nuts you remove the eccentric washers from the nut side as well. They have a flat cut in them that locate them on the bolt, so sometimes they can hang up and add some resistance to pulling the bolts out. Then on the bolt side get something under the washer to pry with. If you can pry at the same time you're trying to spin the head of the bolt back and forth that will help. If you can get a punch on the end of the bolt and give it a few smacks that will help too.

You've already been using penetrating oil, but heat in the form of a propane torch can be really helpful. Be careful not to light all the penetrating oil on fire. If they're really stuck in there you will need heat, a hammer and a prybar.

And had already been mentioned, sometimes they do need to be cut out. I managed to get them out in one piece on my Challenger, which was originally a Utah car that then went to Florida, it was a rusty mess.