Ya thats a little bit of a loaded question. Keep the doors closed. That will keep it from folding in half. The main thing is that everything is screwed and clamped and all of the gaps are correct when you weld it. Sometimes I leave the gap on quarter to door gap a little wide on top to anticipate a change when all of the weight is back in it and the weight on the suspension. Kind of an educated guess. Support the rear (a little) to keep things from changing while you weld and crawl around in there with your body weight. I wish I was doing that instead of fighting paint match. Hope that helps.