I use those fishing boxes that are clear and see through and you can resize the compartments.

I also use Floriani thread and I used some drawers that I purchased
last year from Ikea. I have three (3) of the cabinets 2 silver & 1 red.

You have to assemble them yourself (or have someone do it for you)
but they are the PERFECT storage cabinet for thread and they are METAL.

Ikea storage drawers

I have pegboard on the wall and use hooks to sort my thread by color

I buy plastic school container with handle. I use pegboard and small wooden dowel that fit into the pb. hole. It is single layer and you can see all the thread in it. They come colors of the color wheel. If I use a color twice, I just label with color maker that I am storing in it. Dollar store,Walmart, K-Mart or Office supplies carry them. I bought them when school supplies were on sale. Tinker