I hope the impact doesn't damage anything inside the steering box, because that's what I used. I can't imagine pro mechanics do this job with a wrench.
Here it is with it's cute little bootie -
View attachment 1411892
The bootie doesn't cover the end threads, and it doesn't seal up tight on the nut, but it looks like it's there to do something.
Is there anything special about the cotter pins on the other end of the pitman arm and idler arm? One of mine has snuck off.
Do you have the QA1 K member? If so, is your idler arm loose in the vertical? The idler arm bracket in my QA1 mount is about 3/32"s taller than the one on the factor k member.