1972 Plymouth Duster Alignment failure

Update: Alright so it's been a week or so since i posted last, and i would like to actually share some good news. Today, just for ***** and giggles, i went ahead and installed my new pitman, idler, and centerlink to the current setup(temporary till bushings come in). after playing with the tie rods and getting the alignment roughly right, I checked for endplay and after finding very,very little, I took the duster for a short spin down the county road where i live, and would ya believe it doesnt squall anymore!!!! as a matter of fact it handles fairly well. I will be installing new bushings, the new k and my oil pan in the near future, but i thought id share some good news. Thanks to everyone for the guidance, and I have a quick question about handling with manual steering. Is it normal for the car to go kinda nuts when you hit a pothole? Seems like alot of slack in my steering wheel. Oh and i will be changing my headers soon, as the current setup is scraping against the idler arm nut ever so slightly( plus it has a bunch of exhaust leaks in it) Any suggestions on an economical set of headers? Ive heard headman, but i seem to get mixed feelings
Thanks again,

Bret