Installing small block from the bottom
Your center link is too low? Too high would make more sense to me. Do your headers go under your center link or something? Your pitman arm looks right for the install. Mine didn't even go on as far as yours and it's torqued to spec and has all the clearance I need. The thin pitman arm nut on mine is practically flush with the end of the pitman shaft. I don't think that's your problem. Either bad part number on it or something else. Got any pictures of what you're having interference with?
Well, so much for the piece of cake. There seems to be an issue with either the steering box or the pitman arm. The center link is too low and the left side header will not fit. This is a replacement (rebuilt) PS gearbox and a new pitman arm. I will recheck all the numbers today. Looks to me like the pitman arm should go on the shaft another 1/4 to 3/8 and then everything would clear.
Your center link is too low? Too high would make more sense to me. Do your headers go under your center link or something? Your pitman arm looks right for the install. Mine didn't even go on as far as yours and it's torqued to spec and has all the clearance I need. The thin pitman arm nut on mine is practically flush with the end of the pitman shaft. I don't think that's your problem. Either bad part number on it or something else. Got any pictures of what you're having interference with?