Make sure the power is disconnected and pull the cover off the panel. Most of the panel boxes have screws to hold the whole unit in. You can pull the whole unit out it there is enough room. Move the breakers around to make sure that one ac unit is on one buss and the other ac is on the other buss. Usually either the left or right sides. If they are both on the same buss they will pop the breaker on the gen unit. That should do the trick. Moving the romex can be sometimes difficult
