Heres my scratch built trailer for WWI prime. Its based off of references from 3-d renders from iaconcity.com
Needs some polishing up, but it compliments Prime very Nicely. I would add some red to the trailer too.
Great start! Personally, I think it needs a little bit of wear and maybe some additional detailing, but the shape you've got looks fantastic.
looks great to me, im suprised you managed to get wheels that are the right size though ive been looking every where
I dig the way the cab flows into the trailer like that. A little sanding and filling on the edges and the seams may help to smooth things up a bit too.
The wheels are from a $2 construction set I got at walmart back in the el cheapo toys. yeah I agree about the polishing up but I think for only my second scratch build its pretty decent.