I just recently got ahold of a 351M which i THOUGHT was a small block just like the 351C. Well, I thought wrong. I finally when and picked up the vehicle is was in and got the motor and tranny out today and lord behold this thing was much bigger than i expected. The motor runs great so I have not completly tossed the idea of putting it in my mustang. So I was wondering if anyone knew what it takes to put one of these in my mustang. Anythings possible, So I'm gonna give it a try. But any advice will be much appreciated thank you.