I ran the Firm Feel fast ratio pitman and matching idler on my 71RR. The only problem I had was the grease zerk hitting the exhaust pipe. I was running TTI exhaust off the stock Magnum manifolds. What I ended up doing is taking a torch with a rosebud, heating that portion of the pipe, placing a 1/2" pipe over the spot and dimpling in that portion of the pipe until the zerk cleared.

I should note I was running the Firm Feel Stage II box with the fast ratio pitman. It was just a little too fast for my tastes for a street car.