It's been twenty-plus years for me, but I saw an armored Lincon Continental convertible (there we go with the theories again!) that I believe was the Kennedy assassination vehicle. Of course, cars, cars, and more cars. Also a Ford Trimotor, a Jenny, and a few other aircraft; railroad locos, etc.; giant collections of timepieces and musical instruments; and historical (stationary) steam engines.
Lincoln's Salem courthouse, stone cottages from the Cotswolds, Luther Burbank's greenhouse (Burbank, Edison, and Harvey Firestone were all friends whom Ford idolized); and so on and so on!
Something well worth a visit to the detroit area.
It was a pretty common field trip destination for my school when I was a kid.