CB, when I rebuilt my cj7 for the first time I stripped it and had it sandblasted. Then put her back together. To make a long story short 5yrs after I noticed the frame rotted out from the inside. That's why on the two cj8 frames I have I had them acid dipped to start out clean. If you cut the bad sections out, is the frame stable enough to take to the sandblaster so he can take a shot at blasting a part of the inside. This will show up the thinner metal before you weld in the pieces (better to catch before rather than later) and give him access to the sections that seem to rot out (skidplate mounting, front curve to rear axle etc.). I don't know how far you are along, just a thought.


