John, do you have a rear bumper? The very coolest old trailer I ever saw was a single wheeled one that attached to the rear bumper. I didn't have an old car at the tiem and let it go. I'm sure you seen ones similar from the 50's. It had about a four feet square box and one swivel wheel in the back. It would be fairly easy to build one. The attachment to the bumper would have to be able to go up and down for change in terrain. The wheels verticle spindle had lots of forward lean {caster] so it would follow. This one was a factory built one, I should have bought it.
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Official member of the L.S.S. I know it's misspelled, they only let me use 16 letters