I thought I would post a quick update for those following along...The quarter panel repair is nearly finished and is turning out nice.
Today - I checked out and purchased some seats that had been listed on Craigslist locally. Thanks to the PY Forums (and Chief in particular), the seats were ID'd as '64 Olds A-body. So now I have a correct set of seat frames and sliders to replace my later-model seats that came with my car.