I've worked on quite a few bikes from this era, I gotta say you have a beauty!! Real, real Sweet.

My response below assumes there's nothing wrong with the wheel.

As with all bikes from this time. I'd recommend checking the frame alignment first. Take the rear wheel off. When you loosen the axle, do the dropouts widen or are they "squeezing" the axle? If the dropouts are more narrow or wider than the Outer Lock Nut of the axle stack, then you need some frame aligning. Next, with the wheel off, on the right side of the bike, take a string from a point on the rear dropout to a point on the head tube. Measure the distance from the string to the seat tube. Now put the string on the same points, but on the left hand side of the bike. Measure distance to the seat tube from this side. If the two measurements you made are off by 1-2mm or more, then you need some frame aligning.

read on here:
Bicycle Frame/Hub Spacing

I would leave all aligning to an experienced mechanic though. They should have more precise tools to accomplish a complete precise alignment, without much frame coercion.

Happy Trails!