Hi...sounds like the Engineered Components Inc disk brake kit. I
installed one of these kits on a 39 Chevy Sedan years ago.
The 3100 (1/2 ton short bed) and 3200 (half ton long bed) spindles are
the same. The 3600 (3/4 ton) are different.
You may need to do a bit of sanding with emory cloth...but then you'll
need to drive the adapters on with a pipe and hammer. As long as they
go on partway without much force, they'll drive on the rest of the way
just fine. Make sure that there aren't any burrs on the spindles,
59s in AZ
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