Wow, Voltaire, thanks for the report! Only a few notes for now.
First, the tower was restored in 1984, after The Secret was written, so it is unlikely that you would have encountered Preiss' name in the bricks. I don't know the extent of the restoration, but it might have disrupted things a bit. Perhaps a giant flagpole was removed from somewhere.
Second, I think you have hit upon the correct interpretation of the shapes as 1443. Excellent job. Even in the unlikely event that you turn out to be wrong that 1443 is a street address, the shapes certainly represent 1443 (or 3441 if we follow 'G h' backwards, but probably 1443).




