'66 Impala SS427

[Marina66SS]

I am new to this site and I thought that I would say hi. I currently have a '66 Impala SS that I just bought back from my dad. I bought the car originally when I was 16(ten years ago) and when I bought it the guy said he had just pulled a 427 out of it and it had 427 badges on the fenders. I am curious as to whether I can make sure it is a real 427 car. I haven't found any build sheet and both the motor and badges are easily replaced so I don't know what it was originally. I know it is a factory SS running the numbers. It has a TH400 on the floor with buckets. It also has a 12bolt. Is there a way to tell between a 427 or 396 car? Is the suspension or frame beefier on the 427 car? Is there a way I can track down factory or dealer paperwork? Also I was wondering about the side chrome. Is this on all SS's or an option? I was thinking about taking it off since I am doing the body work on it now. Thanks for the info guys.