The 3 most uncommon vehicles I have owned
1967 Ford Cortina GT ( early '67, still had non crossflow 1500 engine, 2bbl weber, factory headers. Also had the Lotus Cortina rear diff. ratio.
1967 Jeep (Kaiser) Jeepster Commando. Kaiser had bought the tooling from GM for the V-6 ( 225 Dauntless) , AMC later sold it back.
1976 Fiat 128. ( actually my ex wife's car) 1300 with "Alpine" short gearing for some reason. Engine was a gem, other parts not so much.