The MkI & MkII are both included in FH5 and Forza Motorsport. At the time of FM’s launch this topic had 24 votes.
Ford GT40 MkI and MkII
This model has been represented in Forza games as the
1966 Ford #2 GT40 MkII (FM1 - FM | FH1 - FH5)
1964 Ford GT40 Mk I (FM | FH4 - FH5)