Need experienced users of cargo carriers on back of trailer

I have the haulmaster, I found I had to modify the bar by welding a 16 ga plate as a shim.
The haulmaster fit so loosely into the receiver that I thought it moved too much.
I suspect there is a lot more slop in the manufacture of the haulmaster then I was happy with, in other words, todays one could be 0.05 inches larger and fit fine, or even 0.07 larger and be too tight.