Bed Box as Tongue Box: Mounting Ideas?

I have a bed box from an old truck (that we got rid of a year ago) that I really want to use for the tongue box for my trailer. I like the dimensions because I think I can fit an entire solar panel in it.

Here is the problem:
1. The trailer started as a standard 4' Harbor Freight model.
2. The previous owner added a very long tongue (probably triple the original length) to it. The tongue is taken from a different trailer and is made from 4" box steel. It is about 8 feet long, but extends about two feet under the front end of the camper part of the trailer.
3. The bed box is made of aluminum diamond plate. It is 20" by 42" wide.
4. There is a three foot wide piece of angle steel at the front edge of the camper body that I can weld to, as well as the 4" box steel tongue.
I am just about to start work on a tray, mount, or support for the tongue box, but I have questions for the more experienced fabricators:
I can tie into that 3 foot long piece of angle iron for the back end of a tray, but how overboard should I go on the front end? Would it be sufficient to weld a bit of angle steel onto the 4" box steel? Or do I need more support for that front endge to keep the box from twisting or swaying? And if your opinion is that it will need support, do you have any ideas how to build that support?
Here is the problem:
1. The trailer started as a standard 4' Harbor Freight model.
2. The previous owner added a very long tongue (probably triple the original length) to it. The tongue is taken from a different trailer and is made from 4" box steel. It is about 8 feet long, but extends about two feet under the front end of the camper part of the trailer.
3. The bed box is made of aluminum diamond plate. It is 20" by 42" wide.
4. There is a three foot wide piece of angle steel at the front edge of the camper body that I can weld to, as well as the 4" box steel tongue.
I am just about to start work on a tray, mount, or support for the tongue box, but I have questions for the more experienced fabricators:
I can tie into that 3 foot long piece of angle iron for the back end of a tray, but how overboard should I go on the front end? Would it be sufficient to weld a bit of angle steel onto the 4" box steel? Or do I need more support for that front endge to keep the box from twisting or swaying? And if your opinion is that it will need support, do you have any ideas how to build that support?