I bought these juice brakes to try and see if I could adapt them to earlier spindles. I can't without major modifications that I don't want to do and I'm not building a Merc or Shoebox anytime soon so here they are.
These apparently came off of a 53 mercury and should also fit a 52 as well as 49-53 Shoebox. I'm not certain on the fitment though as I'm not schooled up on these cars.
I started cleaning them up a bit since these pictures were taken.