Center section is Dana 44 in both cases (depending on what year 'Vette). 'Vette rears with the complete suspension and mountings aren't too hard to find, especially the '84-'96 style. I see them on a regular basis when i go to the Hoosier and Super Sunday swap meets. Many times, the matching front suspension with crossmember is also being sold, too. Never got prices, but I don't think they were too far out of line.
