Huck brakes are very unforgiving when replacing shoes on well-worn or turned drums. They have a solid pivot point at the bottom and the shoes don't slide around to better engage the drums like Bendix brakes do.
What I do is tighten up the cylinder stars (2 per wheel) until I can't move the tire by hand, then back them up until there is only slight drag, then drive it for a while until the drums act as a milling machine and form-fit the shoes into the same conture as the drums. Then I adjust them again. You may have to do this procedure two or three times before you match the drum/shoes conture to each other. You will notice an improvement in braking action after each time you do this. Once they match, you will have as good of brakes as any kind out there for a truck like these.
Carl
