Beats Walking

Hello all,

For a project, I bought a mid-80's Schwinn LeTour 12-speed at a thrift store. The bike is quite nice except for the rear wheel. Not only is it out of round, but most of the spokes are quite corroded. (The front wheel is pristine: how odd is that?) So should I try and find a new 27" back wheel, or is it possible to easily install a set of 700c wheels? By my calculations, the only thing I would really have to do is adjust the brake pads down by 4mm. Is this correct?

Thanks in advance!