I'd suggest building a framework out of either 2"X2" angle iron with 1/4" wall thickness or maybe 2X2 square tubing that fits the rear of the frame with a 2" square receiver hitch tube in the middle. Bolt it to the frame with 1/2" or 5/8" Grade 8 bolts. Even if you don't plan on using a weight-transfer hitch, the receiver tube allows you to remove the hitch ball when the trailer is not in use. Nothing hurts like catching a shin on a protruding hitch ball, plus it's a hazard in a crowded parking lot.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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