Reverse or forward,manual, you really need the right shifter with a reverse lock-out and gotta watch the neutral. Just as important is whether or not the RMVB has braking in low or not. If not, it will be easier to hurt the sprag on the street.

I had one on my street Challenger and it was fun for a while. Chirping the tires when it shifted made people wonder if it was a stick. But it got tiresome in heavy traffic.

I was also told the the constant hard manual shifts may not be good for the bands & clutches, especially if they are still OEM material. A good trans person should be able to figure out the best line pressures. Naturally higher for performance applications, especially with aftermarket bands & clutches. But it doesn't have to be as high as a trans-brake application.