If you run old school engines they require maintenance same as newer but may entail more than just a oil change more frequent. How many days was it at the alignment shop?
327 is arguably one of the greatest engines of all time. I have some OT stuff that I like, but I would NEVER put an LS in a '63 Impala. Fix the 327. Probably at this stage put head gaskets on it and go another 100,000 miles.
If you're having trouble figuring out why this tired old engine runs rough and smokes, and you're blaming a front end alignment, I'm gonna go out on a limb and suggest than an LS swap is going to tax your mechanical skills. And I mean that in the best possible way.