I believe it was based on the design that was owned by Qvale, MGR bought the assests. Qvale in-turn bought the rights from De Tomaso.
This was the original car design that spawned into the MG/F & TF as we know. But was also the basis of the X80. Later that was dropped and eventually lead to the SV, again a design bought from the Qvale assests.
