Disc brake/spindle ID

These are 4.5” BC with 1/2” studs. I need to verify the casting numbers, but so far I have no reason to doubt the story that they came off the factory L029 Dart campaigned by the seller.

I bought them to put on a clone car I’m building, but I’ve amassing enough original parts over the years that I'm beginning to think I should look for an unrestored original car. I inquired about Lil Thumper but found that it has already sold.