cool! I just build one of these, around the same model year, although the one I worked on was yellow!
I put in a tourney BB, it is 68.5x122.5 IIRC (the axle was bent), rewrapped the bars, new tires and tubes, and a new saddle, brake cables, and pads. My friend rides it as a "bar bike" and it gets compliments all the time. The frame is reasonably well built, not too heavy, and his appeared to have had the wheels replaced at some time, so it rode very well. Have fun with it!