I went up three years ago on trip to pick up a car in Dearborn. While there found a guy with a two car garage packed with nothing but 71 - 73 parts and bought all I could fit in truck, bed, on top of bed cover and in the car.
I was a little disappointed in the show. Not many cars and most were new. I just do not get into showing a brand new car. I can go to the car lot and see them. Sure nice to have but why show it??
I stayed away from the cruise too many crazies, lol. Did not even go to Mustang Alley.
Did spend a day at the Henry Ford and the village enjoyed that more than the show.
Not really a long drive pretty easy one day drive from N.C..
If you go pick your route and then get on Craigslist and look for stuff you need. As you travel then you can stop look and maybe pick up some good buys. I have done that several times with great success.
You find much better interior parts in Michigan than in south or south west where they get cooked.
Even place ads on CL along your route I have picked up two tilt columns that way. I also found the removable hard tops for the early Mustang that way.
Use lots of key words in your ad so it comes up in lots of searches.
I don't think I get but maybe 10 mpg on the vert that would be expensive trip, lol. Would cost less to dolly with truck.