64 Step side project/info

[Chippy126]

Hi All,
My first post, I traded a couple of guns for 64 step side. I have pulled the motor and transmission and am going over numbers. The owner told me it had a 327 but I don't think it is. The numbers, from what I can find, come up as 350.
I plan to rebuild it regardless. I am new to this and have a few questions.
1. Is there a way to tell what the trucks original engine and transmission was?
2. Is there a way to ad AC? I am in SC and its hot on Sundays.
3. Regardless of how it came from the factory has anyone put a three-speed on
the column?
4. Where can I find some detailed original pictures so I have an idea how
moded this old girl has been.
Thanks for any help, I know its a lot in one post.
tried to ad a photo, not sure I did that right.