TNGW1500SE _ I am assuming the OP has the largest air conditioner he wants to use being fed by the 20AMP side so he wants to swap the two zones so the 30A side is feeding his air conditioner he wants to run???
The standard RV 30A to 50A adapter has the two HOT ZONES shorted together in the 50A side of the adapter. This then sends 30A power down both 50AMP zones in the trailer. Of course if you draw more than 30A by using both zones the 30A breaker on the pedestal will trip. But at least both zones are powered up inside the trailer
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Using the dual cheater cable, one zone will be fed by 30A source and the other will be fed by 20A source...
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Guess that all makes sense haha...
Roy Ken