What should be done with this 70 340 Duster

I am not sure on the tire size they are 15 x8 wheels. something tells me n50's but I am not sure . They were originally on the orange Duster.

IF I fix it. when its done it will be a rust free car with eveiy original spot weld in place. The parts cost are going to be the deciding factor.

dont want to derail the thread but what size are the rear tires/wheels in that pic of the red duster?

i honestly think you should fix it.