SSIS: Slowly changing dimension with lists (one-to-many relationship)
I think that in order to keep the logical aspect of a dimension you should use a third table to relate both dimensions:

PersonScd                     GroupOfCars               CarScd
---------                     -------------              ------
PersonBK      &lt;---------&gt;                       &lt;-----&gt;  PK_Car 
Unique_Person_code                                       Unique_Car_code
First Name                     Unique_Car_code            Year
Last Name                      Unique_Person_code         Make
Age                                                       Model
Street Address                                            Color
City                                                      EffectiveDate
State                                                     ExpirationDate
EffectiveDate                                             
ExpirationDate


*
Unique_Car_code and Unique_Person_code are not foreign keys but unique_numbers used to identify a unique car or a unique person.