I've owned & raced 3 feds in the past along with my current altered and none of them had a rear trans mount. They all had a front motor plate and block plate for support and all worked fine. My view is that having 3 attachment points, front and block plate and rear mount, puts more stress on the trans if there is any frame flex when power is applied. At that point, the aluminum trans case would be the weak link and the first to fracture. Wouldn't want that happening down between my feet and legs:)