Put the wrong one in first. The autoparts place gave me one for a Scamp, which is identical to the Challenger except that the pitman arm splines are 1/32 smaller. Had already put the box all the way in and buttoned it up, saving the pitman arm for last. Thats when I discovered the gaffe. Had to go get the right one and reinstall. Thank God for air tools! Anyway, it steers a whole lot better now. Next up, wire in my tach.