Tyres.... sorry Tires question
How wide are the rims on the car. If they are 4.5 to 5.5 inch you might not be able to wider than 205 or 215 max! You might also need a new speedometer pinion if you‘re worried about your mileage/speedometer being off.
Yeah I’d say your Dart is a 1973 given that front end. Does the VIN have a ‘3’ or a ´2´ as the 6h digit on the dashboard?