What could go wrong? Cross country trip

Thoughts on downfalls, if he actually goes?
Not really.
I'll take @TT5.9mag word that this won't test the relationship too hard.
Depending on the time and money available, it may change the nature of the visit somewhat.
Hotels, restraunts, fuel and tolls can add up! :( And yet if your going to drive across the continent, stop and see things for sure. Enjoy it.
Can always camp and cookout but not everyone is into that.
P.S. Bayville is South Jersey, except maybe if your from Cape May. LOL

As far as the car goes, it should be fine.
Rear should go forever unless its been abused. Tires good? Wiper inserts fresh? Points and condensor decent? Good condensor is the only thing that will be difficult buying at a parts store.
If you want to take a spare VR and ballast, they take little room. Same with an ECU if its converted. Ballast shouldn't fail unless it gets splashed with cold water.
I assume he knows how to engine brake in the mountains and understands the gages well enough to interpret the info.

Headlight circuit is really the only one so weak it might have issues under continuous use. So if a lot of night driving, then add a relay harness. A pair of Hella Vision plus lamps with a good bulb and some aiming will be a good balance of readily available and better lighting than most. Or you can ask Stern what he has available that is better.