Given that choice and assuming both are in pretty much the same condition and priced similarly, I'd go with the '83.
The '72 frame is straight gauge while the '83 is double butted (both are chromoly), and the '72 has a heavy one-piece Ashtabula crank while the '83 has an alloy 3-piece crank and generally lighter, smoother action components.
__________________
- Stan
my bikes
Science doesn't care what you believe.