[piecesparts]

For the header nut issues. Try putting teflon tape on the header bolts and then tighten the nuts up snug. Start the truck and warm the pipes up to operating temp and check the tightness one more time. It works, the teflon tape will keep the bolts from backing out and the nuts will stay tight. once set, they stay until you loosen them. If it is on bolts that the Y pipes mount to, then double nut them to have them stay.