is it all worth it?

ive been VERY heavily debating this topic for quite some time and finaly want some outside opinion. i have a 73 dart swinger slant six auto... mechanicly sound, but has some major rust issues in the rear from being parked under a tree for 10 years by the previous owner...so i fixed it up and its now my everyday driver...but im just wondering....is it worth it to fix the body? i was told by a semi reliable source to just ditch it and drop my motor in a rust free shell...that these cars are so common its not economicly worth it to resore a body...especialy in my condition


thoughts?