First I painted it all black. Based on past experience, the red fades to a feminine shade of pink in about a year. I build the front half of the trailer - 4x4 section of frame and tongue assembly - then relocated the spring hangers and used spare parts from the un-built back half of the frame to build a spine from the hitch to the rear crossmember for additional strength and to support a receiver that I can use to mount accessories like a bike carrier.
It's gone through gyrations. I first built an expedition-type box on the frame, but found it was too limiting. I took off the box, extended the frame 1 foot toward the front and extended the hitch 1 foot to make a flat bed sort of trailer. More useful, but I was still dealing with wet tents and other camping stuff. Finally took that apart and built a simple 4x4x7 box with door, windows, bunk with lots of storage underneath, and upgraded to 15 inch wheels. Tows great behind my Jeep Wrangler up a low standard dirt road and provided two nights of really comfortable camping so far.
If I did it again, I'd get the lighter 4x8 trailer and use the full length instead of chopping it down. My current setup is very maneuverable and will hold quite a load, but it tends to bounce over rough roads instead of having the suspension absorb the bumps. Angling the upper front would help with the aerodynamics, but it pulls well as-is.
