I have a axle strap that I use on the rear frame center and attach two straps from that to the trailer.
For the front I tie off same to way. only using an after market chassis kit on bottom of car if you don't have one use the a arms but make sure it pulls as close as posible nearest the frame.
The wheels would be best but is not very practical most trailers are not set up with the correct points to strap down the wheels without pulling on them like you said Brad.
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