Hi @joseanon! Thanks a million for playing through and pointing this out.
However, I've run part 77 through three separate solvers, and they all come up with the "2f654..." SHA.
I think your solver or editor may be stripping a final linebreak (i.e., a linebreak just happens to be the last character). When I remove one from the end of my result, I get your SHA.
(I'm surprised part 78 deciphered correctly for you without it!)