First, this ain't a Dart hood! Strap that thing to some strong supports before even thinking about removing bolts. Better to have a couple strong friends.
Next, try to get a manual or at least some info online. They did things a little different back then.
Here's one source.
http://www.imperialclub.com/Repair/index.htm

Now, soak all bolts with good penetrating oil. 40 year old bolts are easier to remove than 60 year old bolts.
After that, take a good look at how it's mounted and make alignment marks.

Then remove the bolts and remove the hood. To remove the springs from the hinges is a separate ordeal. Be Careful, they are STRONG!