rear brake drum adjustment clearence drag ? problem ? 74 valiant

update : so far so good did a 20 or so mile trip yesterday was fine until half way after i stopped for 10 minutes somewhere . then brakes were shaking a bit up front . after i got home and 1 hour cooldown , i backed off the fronts a little and drove today for about 14 miles with no problems . gonna do another 20-30 miles tomorrow . so , if all goes well , i will attempt the 160+ drive to Carlisle Mopar show on Friday morning . thanks everybody . see ya there if you're going :)