Idler arm hits on header

I have Hooker Headers on my Duster and they were a pain in the *** to line up and fit. The passengers side fits easier than the drivers side. I had to lift my engine about 6" in order to get the headers to line up. As for your fit issue this is the 1st time I've seen any headers on an A Body be off so much. Maybe the motor mount rubbers are worn to the point that when the weight of the engine is resting on the mounts, that the headers are being compressed down and thus squeezing the idler arm? I do not know man, wish I could help you. Mine fit fine out of the box.