Welcome Stephen from our 300Cs in WV! The "pull to the right" has been a common problem, particularly in early build '05 models. There is a Technical Service Bulletin about it, and IIRC alignment isn't the final answer. It has something to do with the cradle position of the engine mounts. I will try to find some info through search and edit this post with whatever info I find.
Fortunately we haven't had the issue with either of our 300Cs.
Welcome aboard. There's lots of help here.
Here's the first of a few...
? on pull to the right
Long thread about
Right Drift Corrected
ResumeSpeed's list of
All TSBs. You have to search down through this list to find specifics. I'm not sure which particular number may be the "final" answer to the early build issue.
Good Luck.