So, you like to abuse equipment and use them beyond their ratings, that we could tell from your original post.
An F550 isn’t rated to pull 20+k from its bumper. Even its 5th wheel configuration is only rated to 22.7k, and that’s in a very specific configuration, and usually it can only handle no more than 16k.
I think you are confusing bumper hitches with frame mounted hitches, but even then you are way off.
Maybe you shouldn’t be making your own trailers. The highways have enough broken down disasters hurting people as it is. Have you gotten that thing inspected and registered?
You have a serious reading deficiency.