You can ask a moderator to change the name on the thread and relocate if that is what you want to do, or you can start a new one elsewhere--its your choice.
If you look at the many discussions about lifting the shell, you will see that there are many forums members that insist that wooden cribbing must be installed to "hold the shape" of the shell. Others will tell you that this is unnecessary--I am of this camp. The C-channels that go along the sides of the trailer wrap around under the plywood, so the bucked rivets int these need to be drilled out. The C channels that form the curve at the ends of the trailer do not go underneath the plywood, so don't drill out these rivets. The shell will hold its shape just fine without bracing on the interior--the ribs, formed segments fore and aft, and the C channels fore and aft do a fine job of this.
The gantry lift can be intimidating just from the shear largeness of the operation, but having done mine this way, I can assure you that this is the way to go. You will get a lot of use out of the lifting frames. I feel like I've become the mad prophet preaching the benefits of the gantry to the masses, but I promise I don't have anything to sell!