I'm a bit late to this party, but I can say a few things from experience with my '93 LX. I put in a Torque Arm and Panhard bar about 2 months back. WHen those went in the UCA's and Quad Shocks came out. Soon after I started hearing pops and creaks that got worse and worse. Not knowing about this Torque Box issue I had the Spring Isolaters replaced (they were shot anyway) and greased up my new UPR Chromally Adjustable LCA's. All this didn't change anything.
I then found out about this torque box issue but didn't find any torn metal in the torque box area. I ordered up Wild Rides Battle Boxes and installed those. Unfortunately nothing changed. Just bolted in didn't help a bit
I just got the battle box and torque boxes welded today and it helped a lot, but it didn't fix things. I still have some creaking and popping going on in the back. I looked things over today and I cleaned and painted the welded areas. I think there are some areas/seams I going to get welded and I hope this shuts this problem up for good. I know my torque boxes are tons stronger than they were, but the noises from back there still make me a little uneasy when driving "spirited".
Below is a link to some pics of my install, hope you find them useful.