I’m right in the middle of doing a 46re in my D100, I have a T56 magnum going in my dart, I’ve used 700r4, 4l80e, 4l60e, and one ford 6r. The “best” one for you will be entirely up to you. I dont care much about sheet metal work, I’ll cut the car to fit the trans. Other guys don’t want to do that, but the cost goes way up if you buy a direct fit 2004r specifically made for your car. So it’s personal preference really.