Well you know that GM's Arlington Assembly Plant is a stones through away from the border with Mexico. A Sequencing label goes on all the Truck frames with the proper country of origin, including the ones made in USA.
I worked at the Fort Wayne Assembly plant during the GMT 900 Launch in 2007. The frames came from about 10 miles away. Whenever a frame got damaged during the frame turnover process the frame supplier would send in an "experienced" rep to beat the frame that back into shape as it was moving down the line.
Scrapping it it would be way too expensive. If they were to pull a damaged frame off the line, they couldn't get a replacement in its place as it would have moved to far downstream in the process. It would be a disaster, throwing the entire production build sequence into chaos, screwing up the line side for all sequenced parts like headliners, seats, instrument panels, door etc. etc.
100% chance that mistakes would be made on the vehicles built for the rest of the shift. (heck you might get an option you didn't pay for, or lose one!).
I saw some real beauty frame repair jobs. Afterwards, (after all the torch heating and hammer pounding ) they would just spread some black frame wax over the repair and SHIP IT.
Would not want one of those trucks in my garage, but stuff happens, and the Plant Quality Engineers have little power to prevent it. Many times I put a truck on hold only to return a few hours later to find it gone! It had been SHIPPED with a note to the dealer to fix it. LOL