Harmy said:

The subtitles in PG are cropped at the bottom and there were never any official 16mm releases, so the subs weren't added to the print, they were copied onto it along with the rest of the picture. Period.

It's quite possible that there were different versions of the subs as well as the credits but at first glance these seem the same to me, only a bit underexposed (like the rest of the picture).

The PG subs are definitely the real thing, Harmy. It's like you say, difference in exposure.