Are you sure you want a 26" frame? You would have to be very tall to ride it. Usually frames are measured from the center of the top tube to the center of the bottom bracket. This would make someone who couls ride a 26 near 7 feet tall.
I have access to an old Continental in good shape, but I'm guessing it is a 23 or 25. If you are interested, I will measure it.
That would be a tall bike! I'm 6-1 and ride a 24" 1980 Conti. At 24" it's a little tall for me now as I've shrunk an inch or so since buying it new! I just really like the feeling of sitting up high on it.