The backfeeding of the panel is what I would be most concerned about. That would mean that each time you used it, you would have to turn off the main 30 amp breaker which is fed from the main power cord, and then turn on the breaker that is backfeeding the panel from the truck generator. I can virtually guarantee that at some time you will forget, or do it in the wrong sequence or someone else will and you will wind up with a live male plug either in the truck or the cord storage compartment.
Use an automatic transfer switch please. Wire it into the cord that feeds the AS, and no additional breaker will be needed in the original box. When off, it will take power from the original cord. When the generator is running, it will automatically take power from that source and de-energise the original cord. Safe, foolproof, and only about $50 to $75 for a 30 amp model.