My hinges say BJ on my 64 and my manifold says FJ25.. So it's normal, your gonna make it! Breathe!
Now is it normal that all of us still have all the old junk? Prolly not! It's an illness I tell you.. An illness!
Looking at Marv's BJ pickup the hinges look nothing like the one's on the 25s and early 40s. But since the BJ4X were fifteen years after the 25 were history I think the BJ has more to do with the original BJ than the BJ4X.