2 steps & transbrakes
Circle D Transmissions built us a HD 4L60E with a T-brake and it held up great. We used it for 2 seasons running the index classes. It is a sportsman brake also. There's only a hand full of transmission shops that can install a TB in the 4L60E.
With that being said, the biggest problem you will run into is going to be traction. The low 1st gear of the 4L60E will had you blowing the tires off or putting the car on the bumper. The 10 bolt won't last a day using the TB.lol.

