i found a 1973 mustang mach 1 for sale. the engine may or may not run not sure as it cant be tested till a battery and a belt are put in. the body has enough rust on it that it needs to be totally stripped. there are 2 rust holes that would have to be cut out and have new metal added and it needs a new trunk floor. the frame is in good condition. the interior needs to be redone totally. the seller wants 4000 for the car but i'm not sure thats a good price could someone help me get an idea of the worth?