Here is my plan at this point. I’m going to use a Harbor Freight 4’ by 8’ trailer, but I am going to have to modify the trailer to match the profile. As you can see in Figure 1, the profile doesn’t meet the trailer at a 90 degree angle, and this causes some complications, being that the bottom length is shorted than the trailer length.
Figure 1
I will need to shorten the trailer length by moving the rear crossbeam (shown in pink in Figure 2) forward to match the bottom length of the profile.
Figure 2
Other trailer mods are I am going to do are to take the 2 center crossmembers (shown in purple in Figure 2. there are 2 there if you look closely) and use them to reinforce the side beams to make it non-foldable. This is described
here.
This is a picture of what someone's reinforcing mod looked like.

I will probably put in a wooden crossmember to replace the 2 I am removing/repurposing.
I will scrap all of the pieces highlighted in orange in Figure 2.
Moving the back beam forward (and shortening the trailer length) reduces the distance from the back of the trailer to the axle (see Figure 3), to about 28% of the trailer body length. I ran some calculations in the
balance spreadsheet, and it seems that it should be fairly easily keep the weight on the hitch below the max tongue load rating and between 10 -15% of the trailer weight. Although, I haven't planned out the Galley or any of the internal stuff, so I'm not really sure how that will play out yet.
Figure 3
Factory dimensions are shown in Red, and the Mod is shown in green. I will cut the side beams off where they stick out past the rear crossbeam.
It seems like all these mods can be done with only the need for basic tools and skills (which is where I am at). I think it only requires a hacksaw, drill, and file. Although I think a drillpress and metal grinder may be better.
I haven't done
any of this yet, I'm just starting to design. So, if anyone has any input based on these mods (tips, warnings, pointers, cautions, etc) I'd love to hear them. Specifically what do you think about the axle only being 28% of the distance from the back. And, what problems I may run into with these Mods. Thanks!