My 1972 Dodge Dart

Looks like someone was building a drag car. Mini tubs for bigger tires, no fenderwells for fenderwell headers, a lot of spare tire wells get cut out due to rot but also when guys want to mount a fuel cell. You have a bit of work ahead of you but if you're good with a mig welder it can all be done and the replacement pieces are out there. Consider your exhaust choices NOW before repairing those fenderwells. You can get underchassis headers but they are pricey. Fenderwells are available but they require small front tire, otherwise they will rub. bigblockdart.com has TONS of big block a body advise - go to their tech pages.