Ok, this is my first attempt to build a chassis and I wonder what went wrong. I'm building a SBC powered Triumph Spitfire, and using a narrowed Ford 8.8. The car originally had IRS so the rear half needed to go bye-bye to install a 4-link.(plus it was super rusty) Anyway, I cut the frame off just behind the front body mounts and replaced it with a homemade chassis made from 2x3" rectangular tubing. I built it using a square and the floor in my shop. As I tacked everything together, I measured over and over again and checked my angles with the square. After everything was tacked, I began to weld everything solid. I moved around to different seems so as not to put too much heat into one area at a time. After everything was said and done, it sat nice and square on the floor. So after everything was cooled, two days later(today), I notice the whole thing was slightly twisted. The passenger side corner is now about 1/8" off the floor. What could I do to prevent this from happening in the future? What did I do wrong? To me this is a giant learning experience and I'm not sweating it too much. This car is likely to be a "prototype" for the next one. Do you guy's think this will affect the cars drivability or it hooking up at the track? Thanx for any inputs!