You need to check with Rudy (rcompart) on this forum. He has a C 240 with an SRT 6 engine mated to a 4matic tranny. Like all of his work the car is awsome. I rode in it at the Dragon a year or so ago and it was a surprising preformer. I know it was for sale at one point and Rudy was looking to get back in an SRT 6.
Could be a win/win situation.