It seems difficult, though? You have to go through layers and layers in the supply chain. It's hard enough changing your own problems, let alone changing how everyone else works.

Lean is mostly about figuring out where your biggest problem is and then disproportionately applying resources to solve it. The biggest problems are typically where there are the most people and the most discomfort due to bad processes. By solving that problem, you're not only improving the flow and velocity through the value stream, but you're also becoming an evangelist for Lean. People see that when you apply these principles, behaviors, and tools, you achieve success. It may sound unwieldy, but a well-run value stream analysis that allows you to look at the whole thing and find your biggest problems is not overwhelming. In fact, it's pretty easy because you get to tackle the most significant issues first and then hone in on the smaller things later.

How do you change the assembly?  

It involves moving the manufacturing process closer together. For instance, if we have a large warehouse between us and where we manufacture the plastic, we could buy a building and move the machine right next door or even inside our facility. This way, as the plastic is molded, it can be taken straight to the line.