I did a quick search and found this thread. Apparently, the springs were not part of the Huck brake assembly after '48.1950 Huck 3100 truck brakes
I have a few follow-up questions for you:
Did the parking brake work prior to installing new brake shoes/cables?
Are the new shoes exact replacements as compared to the old ones?
Are the parking brake cables secured at the backing plate and on the frame rails in the clamps?
Are the new parking brake cables the same length as the old ones?
Is the eccentric bolt adjusted to the high side?
Here's another image that I found on the internet related to the Huck brake assembly.
Let us know, thanks.