I feel like I should go ahead and make one thing clear:
I do NOT want to pile these cars onto the Muscle Inc scene as far as challenges and races go. If I did that, people would want to run them in the challenges, and that's not what the challenges are for. The purpose of the Muscle Inc Challenges is simply the advancement and tuning of American Muscle, which has been made very clear. Perhaps in the future there will be a challenge or other project that includes these cars, that's completely up to DD and Blooze.
Now, I WILL continue to run informal rooms that are open to any car made before 1976, Muscle Inc or FCT. The only restrictions I set on the room are B-Class and older than 1976. I try and discourage the missile cars and am not impressed by 1000hp Chargers. If you bring one into one of my rooms, don't be surprised if I choose Maple Valley Short Reverse or simply ask you to change cars. I can build and have built 'Missiles' out of FCT cars but don't personally enjoy racing them unless everyone in the room is running something similar.
So, if you want to race old Ferraris and Jaguars and Porsches (oh my!) just build it for B-Class and send me a friend request. I start a room almost every night and run till I get cross-eyed!