2006 CTD 5.9 2500 mega cab 4X4. I'm trying to replace the u-joint that connects to the hog head on the rear drive shaft. I have heated up the u-joint so that string crap melts and comes out and have soaked in in penatrating fulid for a day now and I can't seem to get the thing to budge no matter how I go about getting it apart. Any tips or tricks???

P.S. I have dropped the shaft from the rear end.